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Protecting plants from frost is easier with good garden planning. In this post, we’ll talk about DIY cold weather protection for your garden in early spring, fall, and winter to protect your plants from frost. Our cold weather protection for your garden, includes cold frames, frost covers, greenhouses, and other products; plus frost protection garden planning tips.
- Planning Your Garden to Avoid the Need for Frost Protection
- #1 – Avoid Frost Pockets
- #2 – Use Raised Beds
- #3 – Add Heat with Hot Composting
- #4 – Preheat Your Soil
- #5 – Don’t Rush to Plant Too Early
- #6 – Start Seeds Indoors
- #7 – Frost Covers for Plants
- #8 – Water Filled Containers, Such as Wall-o-Water
- #9 – Frost Blankets or Frost Cloths
- #10 – Mini Greenhouses
- #11 – Cold Frames
- #12 – Greenhouses
- Plants That Survive Cold Weather
- Don’t Forget About Low Input Storage
- Ways to enjoy your garden in winter
- Planning Ahead
- How to Protect your Plants from Frost
- Choosing the right Plant for your Garden
- Initial Planting and Plant Care Considerations
- Protecting Different Types of Plants
- Recommended Materials to Protect your Plants
- Build a cold frame or greenhouse
- Damaged Plants
- Perennials Grown as Annuals
- Dealing with Snow
- Frost And Your Plants: What You Need To Know
- How to protect container plants and pots from winter frost
- Move tender plants
- How can I stop pots cracking in frost?
- Winter Container Gardening
- Bubble wrap for insulation from heat
- Wrapping Plants In Burlap: How To Use Burlap For Protecting Plants
- Burlap Plant Protection
- Covering Plants with Burlap
- What Plants Need Burlap?
- How to Winterize Shrubs
- How do I protect my trees and shrubs from winter damage?
Planning Your Garden to Avoid the Need for Frost Protection
Good garden planning and preparation can help avoid the need for frost protection, or be used in combination with frost protection for plants.
A microclimate is a small area with a climate that differs from the surrounding area. In the case of frost protection, you want to warm the air and soil where you’re planting, and shelter plants from excess wind and temperature fluctuations.
A good microclimate can give your garden a boost in spring and fall. In spring, it gives you an earlier start, in fall, it can buy you a few degrees to ward off light frost, especially if combined with elements like floating row covers.
#1 – Avoid Frost Pockets
Frost tends to settle in low lying areas. If you have a choice in elevations for your garden, opt for a higher spot to avoid low lying frost.
My gardens are a great example. Our south beds are around 20 feet lower than the beds on the north side of the house. The south beds will freeze while the north beds are still intact. The north beds are more exposed to the wind until our treeline gets taller, so there are pros and cons to both locations.
#2 – Use Raised Beds
If you don’t have a high spot to plant your garden for frost protection, make your own. Raised beds heat up faster and stay warmer. (For those who face the opposite problem (too much heat) planting in troughs can provide cooler temps and wind protection.) Raised beds tend to dry out quicker, so plan accordingly with watering and mulch if needed.
#3 – Add Heat with Hot Composting
One old technique for frost protection (and boosting plant growth) was to place partially finished compost or composting manure in the center of a raised planting bed. The heat of the working compost to warms the soil for planting. Don’t plant your seeds or transplants directly in hot compost, as the heat and excess nitrogen can kill plants.
#4 – Preheat Your Soil
Another way to add heat to your soil is to cover the ground with plastic or other dark material. This raises the soil temperature so you can transplant earlier. Preheating the soil promotes better germination rates and easier transplanting.
Clear plastic warms the soil well, but can promote weed growth if it isn’t hot enough. Black plastic mulch is commonly used, as it is cheap and blocks weed growth. Recently, IRT (Infra-Red Transmitting) plastic mulch has become available, which blocks visible light but allows infrared light to pass through.
I always use black landscape fabric in my melon patches. Depending on the season, I may also do it for other heat loving crops such as cucumbers, tomatoes, summer squash, and eggplants. Some plants, such as corn, might like warmer ground temperatures to germinate, but cooler temperatures while growing. Make sure to check preferred growing temps before you put down soil covers.
#5 – Don’t Rush to Plant Too Early
Even when air temperatures are above freezing, ground temperatures can lag behind, so don’t rush to plant too early. To learn more about the your planting conditions you might want to read this article: Plant Hardiness Zones and Microclimate – Creating Your Best Garden
#6 – Start Seeds Indoors
Figure out the average date of last frost in your area by checking with your local extension office or researching online. Then check the seed packets of your desired crops to see which ones are best started inside before setting outside as transplants. Count back from your average last frost date the appropriate number of weeks to determine your indoor planting schedule.
*Note: Don’t forget to check whether your seeds need to be stratified to improve germination. Stratification is the process of placing seeds in cold storage for a time to mimic the natural freezing process. This is more common for herbs and wildflowers.
For instance, many slow growing herbs and flowers suggest starting indoors 10-12 weeks before last frost. Tomatoes and peppers may suggest 4-8 weeks before last frost. Vine crops may be started inside 1-2 weeks before last frost (if the plants get too large they do not transplant well and are more likely to get transplant shock and be set back). You can also start seeds for fall plantings inside when it’s too hot for them to germinate outside.
For more information on seed starting, see:
My Favorite Seed Sources, Seed Storage and Germination – Printable Seed Longevity and Germination Charts
When Should I Start My Seeds? Printable seed starting calendar
How to Grow Tomatoes from Seed
#7 – Frost Covers for Plants
One of the cheapest, easiest frost covers you can make is to cut the bottom off of a gallon plastic jug, such as a vinegar jug. Simply slip the jug over your seedling and wiggle it gently into the ground. If it gets warmer during the day, open the lid for ventilation. When the danger of frost is past, remove the cover for a few hours each day, extending the time left uncovered slowly to give your plant a chance to adjust.
If you’d like an option that’s a little more attractive, gardening supply stores sell glass or plastic cloches in a little bell shape with handle for easy use.
#8 – Water Filled Containers, Such as Wall-o-Water
The wall-o-water is a series of plastic tubes connected into a cylinder that fits over your seedlings. The tubes are filled with water. When the temperature drops, the water in the plastic tubes freezes instead of your plants.
See Wall O’ Water 12 Pack – GREEN
You can also make a homemade version of the wall-o-water products. Fill empty plastic jugs with water, and use them to create a wall around a transplant (for instance, around a hill of melons). If you don’t have enough to completely circle the plant(s), use the jugs to block prevailing winds. I use gallon jugs from milk and vinegar; I’ve seen others use two liter soda bottles. These will typically last several seasons before ending up in recycling. (Vinegar jugs are much sturdier than milk jugs.)
#9 – Frost Blankets or Frost Cloths
If fall frost is threatening to cut your harvest short, an old blanket or tarp can be draped over plants for frost protection. An air gap between your plants and the frost blanket adds more protection. You can add the air gaps by combining the frost blanket with a hoop framework to form a garden low tunnel. I have a friend in a slightly warmer climate who keeps cold tolerant greens growing in her garden tunnels all winter long.
See Agfabric Warm Worth Floating Row Cover & Plant Blanket
Can I cover my plants with plastic for frost protection?
Yes, sometimes plastic is used for frost protection. For instance, on low garden tunnels, high tunnels, garden cloches and greenhouses. You need to be careful that your plants don’t overheat when the temperature goes up, because plastic doesn’t breath like garden fabric. You also have to watch out for moisture buildup inside plastic covers, which can increase the risk of fungal diseases.
#10 – Mini Greenhouses
For a small garden, sometimes a mini greenhouse is all you need for frost protection. These little kits are relatively inexpensive and set up in minutes. Just make sure to anchor your mini greenhouse securely so it doesn’t get caught by the wind and whipped away.
There are several different types of mini greenhouses. Some come with shelves, and work best for seed starting, when the plants are small. Others are shorter and wider, and are intended to go directly in the garden. The mini greenhouse in the photo has small access doors on top, but some models open entirely on one side. (This makes access much easier.)
Gardman R687 4-Tier Mini Greenhouse
Quictent Super Large Zipper Doors Mini Greenhouse Portable Cloche
#11 – Cold Frames
A cold frame is a box, typically with opaque walls and a clear cover. It can be simple, such as an old storm window over a rectangle of straw bales, or a custom built wooden frame and cover, or a pre-packaged unit. Most home built units are lower in the front and higher in the back to allow more sun to reach the plants, and sized to accommodate whatever used windows are available. The fronts should be at least eight inches tall so that you have room to accommodate some plant height. We have two cold frames sized to fit old patio doors. *Note: Make sure any old windows you use do not have lead paint on them. Obviously, that’s not something you want around your food.
Cold frames are unheated (except for by the sun). Their primary advantages are to protect from the wind and overnight cold temperatures. When using them (as when using a greenhouse), be careful to vent to avoid overheating on sunny days.
#12 – Greenhouses
I have a small greenhouse attached to the southeast corner of our home. We also added a detached greenhouse in 2015. I transition plants from seed starting shelves inside, to the greenhouses or the cold frames, to out in the garden. The greenhouses have allowed me to significantly reduce the time the plants spend under grow lights. Our attached greenhouse is a simple wooden frame covered in multi-wall polycarbonate, and is built into the hillside as part of our retaining wall so it is earth sheltered.
Our detached greenhouse is also multi-wall polycarbonate, and sheltered at the north end by a combination coop/garden shed. Multi-wall polycarbonate provides more frost protection than single wall plastic or poly covers.
Many different sizes and types of greenhouses are available, depending on your space and budget. A greenhouse may or may not have supplemental heat. See also, “The Forest Garden Greenhouse“.
If you’d like more information on building a greenhouse, check out how we built the foundation of our detached greenhouse. The video below features a greenhouse built from recycled materials.
Plants That Survive Cold Weather
Keep in mind that many crops will tolerate cold weather, and some (like kale) even improve their flavor after a light frost.
Some crops that prefer cooler (but not freezing) temperatures include:
For hardcore frost protection and season extension advice, I recommend checking out Eliot Coleman’s books:
“Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long” and
“The Winter Harvest Handbook: Year Round Vegetable Production Using Deep Organic Techniques and Unheated Greenhouses“.
Don’t Forget About Low Input Storage
From my perspective, it’s easier to spend time preserving some crops than battling the elements to keep them going outside. My favorites are the ones that hold “as is” with little or no effort. You can read more about these crops in:
- Root Cellars 101
- Above Ground Root Cellars – Enjoy Your Local Produce Longer
- The 5 Easiest Vegetables to Store
- Plant Hardiness Zones and Microclimate – Creating Your Best Garden
I hope you found this post useful. Don’t forget to take a peek at the rest of our Gardening Articles.
If you need additional information on season extension, I recommend the books below.
Originally published in 2013, updated in 2018.
Ways to enjoy your garden in winter
Winter can be a quiet time in the garden, as many plants are dormant. But if your green fingers are itching and you’re craving some time outdoors, there’s still plenty to do in the garden during the winter months. There are also plenty of plants to enjoy at this time of year.
Before you hunker down for the winter, some preparation is key – protect tender plants such as dahlias, cannas and bananas, and bring in or cover garden furniture. It’s also worth planting bulbs for colour in spring.
More winter content:
- Help wildlife survive winter
- What to prune in winter
- Five steps to winter compost
Here are 10 tips for enjoying your garden in winter.
If your green fingers are itching and you’re craving some time outdoors, there’s still plenty to do in the garden during the winter months.
Delicate white flowers hanging along a stem of Sarococca confusa
Evergreens, from box balls and topiary to large, established shrubs, add vital structure in the garden year round but come to the fore in winter. There are many beautiful evergreen shrubs to choose from – browse our Plant Finder for inspiration. Sarcococca confusa, pictured, has the added advantage of strongly scented flowers, too.
Plant bare-root plants
Firming the soil around newly planted bare-root blackcurrant canes
Winter is the time for planting bare-root plants (plants sold without any soil around the roots). It’s an economical way of planting and you’ll find a much wider variety of fruit trees and bushes are available this way. You can also plant bare-root roses, hedges and even perennials. Discover plants to plant bareroot.
Enjoy winter flowers and scent
There are many flowers to enjoy in winter, including Cyclamen coum, hellebores, snowdrops, crocus, aconites and winter iris. The flowers of some plants, such as viburnum, hamamelis (witch hazel) and daphne are strongly scented. If your garden lacks colour, head to your local garden centre, where you’ll find many seasonal delights – find out how to plant winter bedding.
Tidy potting-shed shelves
Spend a morning pottering about tidying your greenhouse and shed, having a seasonal tidy up. The greenhouse is less full at this time of year, so it’s a good time to prepare it for spring. Service or maintain your mower and sharpen your tools, ready for the busier seasons ahead.
Three terracotta pots of food for birds hung from a tree by string
Garden wildlife really needs your help in winter and there are lots of things you can do – find out how to help wildlife survive winter. Get advice on feeding garden birds in winter and find out how to make your garden bee-friendly in winter.
Make the most of your greenhouse
A wide, flat terracotta planter of sempervivums
Pottering in the greenhouse is a great way to stave off winter blues. Tidy up overwintering pelargoniums, have a go at growing citrus plants, or plant up a pot of succulents. In January and February you can start sowing seeds in a heated propagator. If temperatures plummet, insulate the greenhouse with bubble wrap.
Plant winter containers
A green glazed planter of winter foliage including a red cyclamen and a grass
A few winter containers, planted with evergreens and plants with colourful berries or flowers can brighten a dull winter day. Position them near the house so you can enjoy them easily. Discover 10 winter containers to try.
Prune fruit trees, bushes, shrubs and roses
Pruning a fruit tree in winter
Winter is the main time to prune many types of fruit, including blackcurrants, apples, pears, autumn-fruiting raspberries, redcurrants and gooseberries. It’s also a good time to tackle trees, shrubs and roses. Find out more about what to prune in winter.
Honesty seedheads covered in frost
Many perennials are cut back at the onset of autumn, but it’s worth leaving plants with attractive seedheads, such as rudbeckia, teasels, echinops and ornamental grasses, intact so that you can enjoy their unique beauty over winter. Cut down in spring, when you see new growth appearing at the base.
Keep the veg plot going
Freshly harvested parsnips Advertisement
Crops to harvest in winter include parsnips (which taste better after a frost), kale, Brussels sprouts, leeks, winter cabbages and winter salad. If you didn’t get around to planting winter veg and salad earlier in the year, you can grow pulses indoors, as well as microgreens, ready in just a few days. You can also plant for future feasts – garlic, fruit bushes and raspberries and rhubarb can all be planted in winter.
Don’t let the winter ruin the beauty of your garden. Take care of it using the tips you can read in the following section. Maintaining your garden in this cold season, after all, can also prepare it for when spring and summer come.
So, if you’re ready, let’s begin highlighting the things you can do to maintain your winter garden.
Removing spent plants
Cleaning up finished and rotting plants is one of the best ways to keep your garden healthy in the winter. Removing old plants will not only tidy it up but also prevent the spread of fungi, pests, and diseases.
Getting rid of spent plants and then burying those disease-free finished plants can prevent most garden pests from spreading when the spring comes. In addition, burying them will also improve soil health as they can add organic matter to it.
Pruning in winter
Pruning helps remove dead plant in order to promote the growth of larger shoots for the coming growth season.
When pruning shrubs and flowering trees, you must prune the autumn and summer flowering shrubs and trees in the early spring and late winter. You must also prune those when their flowers started fading.
Also, you should be pruning deciduous plants for their spring re-growth because many of them are inactive or dormant in the winter. And as the foliage of the plants is gone, it is easier and faster to see their shape.
For best results, keep the following in mind:
- You should first prune out diseased or dead branches.
- You must also consider pruning on a dry day.
- In order to increase both the air and the light at a tree’s crown, you should remove smaller and overgrown branches.
- Also, don’t remove the branches that keep the tree’s structure and that are developing.
- You should also cut branches at the part wherein a twig or branch is attaching to another.
This winter, you should also learn how to divide and plant bulbs.
Bulbs, including daffodils and tulips, should be planted early in the winter because they require much time before blooming in the spring. These bulbs also need cool temperatures which can speed up their flowering.
For fall-planted bulbs, you should soak them in warm water for 12 hours before planting them, especially for tunicate-type bulbs that have teardrop-shaped or enclosed, round bulbs. However, this method is not suitable for lilies and other bulbs with fleshy scales.
By soaking them, the bulbs will absorb enough water to grow fast, saving you three weeks of time, especially if you’re in a northern climate location. Divide and then fertilize the bulbs to promote their blooming.
For bulbs that have few or no flowers, you might want to divide or fertilize them first. You can also consider using slow-release bulb fertilizers to keep its effectiveness in the early spring.
Use these tips to prepare your garden for the next gardening season. These tips will improve your yields in the end aside from helping you keep a lovely garden in the spring and the summer.
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Author: Cacti landscape
Here are tips on how to protect your garden from frost and design a garden to reduce frost damage—plus, a handy chart listing dangerous temperature lows for vegetables.
To know when your area gets frost, see our U.S. Frost Dates Calculator and the Canadian Frost Dates.
Whether you are waiting to plant in spring or those late fall days are getting frosty, it is important that frosts will not hamper your efforts.
When to Protect Your Plans
If temperatures below 32 degrees F are predicted, protect your plants! A moderate freeze with temperatures in the 25- to 28-degree Fahrenheit range can be widely destructive to vegetation.
Frost protection is especially important for tender plants such as geraniums, begonias, impatiens, peppers, and tomatoes.
- In the spring, use row covers if you have tender vegetable seedlings and transplants in the spring. Row covers or garden fleece can also be used to help create a warmer environment beneath them. You’ll need to use posts or bamboo to create space for the plants to grow, then drape landscape fabric or plastic over the posts; weigh down the edges with rocks or bricks or pegs so the covers do not blow away.
- Alternatively, you can recycle clear plastic drinks bottles as plant covers or “cloches.” Simply cut a bottle in half using sharp scissors, then place the top half over your plant. Keep the lid off on sunny days, or screw it on when cold weather is forecast. Keep your bottle cloches from blowing away by pushing them into the soil or by holding them in place with a cane.
- Cover other established plants with frost cloths or other insulators including newspapers, straw, old sheets and bedspreads, or evergreen branches. Cover the whole plant; you’re trying to retain radiated heat.
- It’s best to have all covers in place well before sunset. Drape loosely to allow for air circulation. Before you cover the plants in late afternoon or early evening, water your plants lightly.
- The plants should be mulched, but pull the mulch back from the root of the plants.
- Remove the covers by mid-morning.
- In the fall, the first frost is often followed by a prolonged period of frost-free weather. Cover tender flowers and vegetables on frosty nights, and you may be able to enjoy extra weeks of gardening.
What Temperatures Cause Frost Damage?
Designing Your Garden to Reduce Frost
Here are different ways through which you can reduce the amount of cooling in and around your garden.
- Your garden will warm up more during the day if it slopes toward the sun. Residual heat in plants and soil may determine whether your garden sustains frost damage during the night. Cold air, which is dense and heavy, will flow away from plants growing on a slope—what the experts call “drainage.”
- A garden on a south-facing slope offers two advantages: more exposure to the Sun, and better drainage of cold air. In deep valleys, nighttime temperatures may be as much as 18°F lower than the temperature on the surrounding hills.
- Trees surrounding your garden act like a blanket and reduce the amount of heat radiating from the soil, perhaps keeping the temperature high enough to protect your plants from early fall frosts. Plants themselves can modify cooling. Place plants close together to create a canopy that entraps heat from the soil (though the tops can still suffer frost damage).
- A garden wall benefits the garden by acting as a heat sink, absorbing warmth from the Sun during the day and radiating it slowly at night.
- Water in a nearby lake or pond (if it is one acre or larger) will also act as a heat sink. A cold frame can be heated with an improvised heat sink: a dozen 1-gallon jugs of water. They absorb heat during the day and radiate it at night.
- Moisture also determines whether frost will nip your tomatoes. Condensation warms and evaporation cools. When moisture in the air condenses on plants and soil, heat is produced, sometimes raising the temperature enough to save the plants. On the other hand, if the air is dry, moisture in the soil will evaporate, removing some heat.
- Good soil, full of organic matter, retains moisture, reducing the rate of evaporation. Mulch also helps to prevent evaporation.
- In early spring, warm up your soil faster by covering it over with plastic, row covers or garden fleece. This technique is particularly useful for heavy or clay soils that retain a lot of moisture. Lay the plastic over the ground at least one week before sowing and soil temperatures will rise by a couple of degrees, making all the difference for early sowings.
- Of course, raised beds will warm up more quickly thanks to the free-draining conditions within them, so if you have raised beds, start your first sowings here.
Design your garden with the Almanac Garden Planner which uses averaged frost data from nearly 5,000 weather stations across the U.S. and Canada. To benefit from this, consider a free 7-day trial to our Almanac Garden Planner!
When the sky seems very full of stars, expect frost. –Weather Lore
If it has been a glorious day, with a clear sky and low humidity, chances are that temperatures will drop enough at night to cause frost.
Find out how to predict that a frost is coming!
See our Autumnal Equinox page for more fall-themed advice, folklore, facts, and fun!
How to Protect your Plants from Frost
Snow and hard frost are naturally characteristic of the winter months. Despite their wonder and splendour and the fun they bring to children, they can be a major problem for your treasured garden plants, damaging new growth and killing tender and half-hardy varieties. Low temperatures capable of harming frost-sensitive plants may begin in November and continue through to February and beyond. Typically in the UK, there may be between 7 and 10 nights where the temperatures are below freezing and plants might be damaged.
Frost and freezing conditions cause the water in plant cells to freeze, resulting in the cell wall being damaged. The most obvious, tell-tale signs of frost damage are blackened, distorted or limp growth and a browning of the leaves of evergreen plants, which makes them look translucent. These issues are exacerbated by morning sun, causing rapid defrosting which can rupture the cell walls of plants. When the ground becomes frozen, the roots of even the toughest varieties become unable to absorb water, resulting in die-back due to a lack of moisture. Late frosts in spring can also damage flowers and fruit.
Choosing the right Plant for your Garden
The best way to seek to minimise frost damage is to prevent it in the first instance, rather than desperately seeking a cure after it has happened. It is advisable to follow several guidelines which will help to minimise losses in your garden when prolonged spells of cold weather set in.
The simplest, most effective option is to always choose plants that are reliably hardy in the area where you live. You can determine which plants are appropriate for your location by looking at Hardiness Zones. The best categorisation system to refer is the RHS Hardiness Zones, which range from Fully Hardy (H) to Frost Tender (FT). The RHS revised its rating system after the severe winters of 2009/10 and 2010/11, so the RHS ratings shown below are up-to-date:
All of the plants for sale on our website are categorised by RHS Hardiness Zone.
The steps to using the RHS Hardiness Zone system are, firstly, to establish the expected minimum temperature in your area; the Met Office website in conjunction with conversations with other local gardeners should be able to assist here. Secondly, search for plants with a hardiness categorisation that is appropriate given the zone where you live. The drawback of this approach, specifically the restriction it imposes on your choice of plants, generally outweighs the potential disappointment of losing plants that are not sufficiently protected when the temperature dips below the minimum level they are hardy too.
It is also worth giving consideration to which parts of your garden get the most sunlight by producing a sun chart, noting that sunlight will reach different parts in the winter than in the summer. Just remember that if a plant faces the morning sun, this can cause fast defrosting, resulting in cell wall ruptures and damaging the plant.
Initial Planting and Plant Care Considerations
Below is some initial guidance we can offer that is often overlooked by inexperienced gardeners:
- Always plant Half Hardy and Frost Tender plants in a sheltered position, preferably near a south or west-facing wall, which will absorb heat during the day and radiate it at night. Other good positions include allies out of the wind, against fences and boulders, or under other large shrubs, trees, roof overhangs, eaves or patio extensions (but not in full shade). Eliminating the wind chill factor can substantially reduce the amount of frost damage incurred.
- Apply high-nitrogen fertilisers sparingly because this fosters large amounts of sappy leaf growth that is highly susceptible to frost damage. Always follow the instructions on the multi-purpose fertiliser packet and do not be tempted to over-do it!
- Leaving on mature growth of Half Hardy and Frost Tender plants over the winter months helps to protect central stems. We recommend you avoid pruning back all except the hardiest plant varieties in autumn to prevent new growth from being damaged by frost
- Microclimates called frost ‘pockets’ will occur in the lowest part of your garden, therefore, it is best to select fully hardy plants for these areas. You may wish to design a garden with raised beds to guard against these frost ‘pockets’, particularly if your garden also has poor soil because raised beds have the added benefit of giving you a fresh start in terms of the quality of the ground you plant into.
- Water your plants evenly throughout the winter. During the coldest months, it is best to water in the morning because wet soil absorbs heat during the day and this also ensures leaves will be dry by the time it starts to get cold at night. As always, don’t over-water.
Protecting Different Types of Plants
Some of the types of plants that need protection from frost include tropicals, plants with soft wood, fruit and vegetables, plants in flower and potted plants. As a general rule, It’s best to start protecting your plants before dark because they will be most vulnerable at night when temperatures drop and moisture is in the air. Make sure you leave enough time to purchase supplies, cover and insulate your outdoor plants, as well as bringing container grown plants indoors. Being prepared for frost and buying the necessary materials in advance will make your life a lot easier and avoid the need for a last minute rush. Some specific guidance for different types of plants is given below:
- Open Ground Plants – Protect your open ground plants using some of the frost protection materials recommended below. Certain plants can be over-wintered indoors by digging them up prior to the first frost and wrapping up / protecting their roots as necessary. We do not advocate this approach because tampering with the rooms disrupts the plant’s growth. Far better is to choose a plant suitable to your hardiness zone at the outset.
- Perennials, Bulbs and Corms – For herbaceous perennials that naturally die back during the winter, bulbs and corms, cover the ground above them with a thick mulch of straw, old leaves or manure so that the soil does not freeze
- Evergreens – With evergreen shrubs, mulch around the base with a thick layer of old leaves straw or manure to ensure the soil stays frost-free. This prevents the soil around their roots from freezing solid, which means they can continue to absorb water when required
- Container Grown Plants – We highly recommend that Frost Tender and Half Hardy plants are grown in containers so they can be taken indoors when cold weather, frost and snow strikes. Wheeling the plants into a garage, sunroom, greenhouse or shed are all viable solutions. If you are eager to continue growing a tender variety that cannot be brought indoors, consider taking cuttings and storing them in water in your greenhouse or outbuilding. An attempt to root them could then be made in the spring. Selecting frost-proof containers is the best way to ensure your pots and tubs do not crack when the frost strikes, and storing them in an outbuilding for protection also helps. ‘Pot feet’ should be used to prevent the bottoms of container grown plants from getting waterlogged where they cannot be moved indoors. If there is no viable option to bring your container plants indoors, cluster them close together in a sheltered spot near the house.
- Cordylines and Tree Ferns – The vital part of tree ferns that must be protected is the crown – the upper part of the trunk from which the leaves disperse from. Leaves should be carefully secured in bunches and covered with ample amounts of protective fleece to provide insulation. An alternative is to position straw around the leaves and upper trunk in bags or netting. When the frost is particularly harsh, consider placing a lamp designed for outdoor use within the interior of the tree. Such lamps can produce enough warmth to reduce frost damage. Non-LED holiday lights can be used instead to achieve the same result, providing you are very careful they do not touch any other insulative materials being used.
- Ground Cover Plants – Ground cover and low-growing varieties can be protected by positioning a layer or grit or gravel around them; this ensures that water drains away quickly. They should also be covered with a polythene clothe or a sheet of glass to contain heat.
Recommended Materials to Protect your Plants
There is a wide range of materials that can be used to help shelter your plants from the frost, many of which are likely to be already readily available around the house. A comprehensive list is provided below.
- Permeable Fleece – use a layer or several layers of protective fleece to provide insulation. This should be made of a permeable fabric to allow the plant to ‘breathe’ and should ideally be positioned on a frame above the tender plants before the frost hits.
- Straw or Bracken Leaves – this provides a natural alternative that can be wedged in thick chunks between sections of chicken wire and positioned around plants to provide insulation.
- Fabric – if the frost is only expected to last for a short time and you do not want the hassle of purchasing special frost protection materials, consider placing an old blanket, spare bed sheet, lightweight drop cloth, thin towel or other large scrap of fabric over or around your plants and securing it with stones on the ground or pins (being careful not the crush your plants). Providing it is taken off during the day, your plants will get the light and air they need. Avoid using heavy fabrics as they may sag and damage the plants underneath.
- Layered Newspaper – lightweight, breathable and insulative, old newspaper is an excellent low-cost source of frost protection. Wrap newspaper around the containers of potted plans to protect the soil from freezing. ‘Tenting’ newspaper over smaller plants using stones to keep it weighted down is also a viable option, although problems are often experienced with the newspaper blowing away if there are high winds.
- Cut-off Plastic Bottles – large (1 or 2 litres) plastic drinks or milk containers are perfect for embedding into the soil around small plants and seedlings to provide protection
- Clothes Hangars (to create wireframes) – one of the difficulties in applying insulating materials around plants is often establishing a frame to secure them to. By bending clothes hangars and positioning them in an arch at the top of the plant, it’s possible to create a wireframe from which your choice of insulative material can be hung. It’s best to ensure, as far as possible, that the insulative material hangs all the way to the ground to ensure maximal heat retention.
- Wicker Baskets – inverting a large wicker basket and placing it over the plant you’re looking to protect can offer a helpful quick solution, over which further insulation can be secured. Alternative sturdy containers achieve the same result.
- Mulching – A thick layer of bark, rotted leaves or other organic material can act as an excellent insulator to protect the roots of your plants. Sometimes it is the freeze and thaw cycle of the soil that damages the plant, more so than the cold temperature above the surface. In fact, certain plants such as rose bushes and strawberry plants can be over-wintered by covering them completely with mulch. Just don’t forget to rake the mulch away again once the danger of frost has passed.
With the exception of protecting very small plants and seedlings (where cut off plastic bottles are appropriate), we do not recommend you use plastic as an insulative material. Although plastic is often used, it is not breathable and can trap moisture, increasing the risk of the plant being damaged. Whatever protective material is used, remember to remove it again when the temperature rises the next day, otherwise, the plant may fall victim to suffocation.
Build a cold frame or greenhouse
Many gardeners find that the option of building or purchasing a cold frame proves attractive and worthwhile. A cold frame is essentially a transparent-roofed enclosure, built reasonably low to the ground in order to protect plants from the cold or excessively wet weather. A temporary cold frame can be constructed by bending slender, malleable metal rods into loops and inserting the ends into the ground across a garden row. This creates a frame over which a sheet of clear plastic can be laid to protect the plants inside. A more permanent cold frame consists of a hinged window on one side of an open-bottomed wooden box.
Although prevention is definitely the best solution, if plants do get frost damaged they may recover given time. To give your plants the best chance of recovery, follow the steps below:
- Cover plants with a layer of black plastic (ideally with multiple pin-pricks made across the plastic sheet to allow the plant to breathe) during the morning to block out the worst of the morning sun. At mid-day, ensure the plastic is removed.
- Encourage the development of fresh, new shoots by cutting back frost-nipped stems to a new bud or node once the risk of frost has passed. Until this time, or until they start to decay, leave them on the plant to protect lower foliage
- Apply the recommended amount of a multi-purpose NPK fertiliser (nitrogen, phosphorus and potassium) to your plants to encourage strong growth; do not overdo it as this will result in excessive sappy growth, making your plants more vulnerable. Mulching with organic matter such as rotted mature, mashed up twigs and bark, peat, moss, old shredded leaves and composted lawn clippings can also be used to provide a more natural, slower release source of nutrition.
- Move damaged, tender plants to a greenhouse. Providing they have not experienced extended frosty periods, they may recover if given the necessary warmth, protection and nutrients
- Don’t give up on your damaged plants too soon. Plants can be remarkably resilient, even if initially they show little sign of life. Wait until the weather warms up in the spring to provide an opportunity for new shoots to develop. If the plant re-grows from the base, cut out the old, dead stems. Only if no new growth has been seen by the end of spring should the plant be considered a dead specimen and removed. In this case, replace with a hardier variety.
Perennials Grown as Annuals
Annuals are plants that die back in the winter each year, but then re-grow the following growing season from their bulb or corn. Perennials are often grown as annuals in colder climates such as the UK, so do not necessarily think the plant has been permanently lost if it dies back for the winter. If you wish, you can extend the growing season for some annual perennials by sheltering their growing position and container growing them indoors, or inside a greenhouse.
We would encourage you to talk to other local gardeners about what to expect from perennials plants during the winter in your area. Alternatively, visit our garden centre in Staffordshire; our friendly staff would be more than happy to assist with your questions.
Dealing with Snow
Finally, some guidance about removing snow from atop your plants and clearing it from your garden. Snow can actually be a help and a hindrance. On the one hand, it has insulative properties, which protect your plants from the frost. However, the weight of thick layers of snow can also cause branches to snap. Be ready to follow the best-practice steps below when snow arrives:
- Remove excess snow from plants by wiping and shaking it off
- Sweep snow from the tops of cold frames and roofs of greenhouses to prevent possible damage under the weight
- Use twine or string to hold the branches of young trees and conifers in place
- Do not walk over your snow-covered lawn. Doing so will leave unsightly marks and damage the grass underneath
Frost And Your Plants: What You Need To Know
The dreaded first frost of fall looms just around the corner for many gardeners across the country. During a light frost, some plants may be killed, with little destructive effect on hardier vegetation. Here’s a guide to frost and how you can protect your plants.
Clear or Cloudy Sky?
Frost (also called white or hoarfrost) occurs when air temperatures dip below 32°F and ice crystals form on plant leaves, injuring, and sometimes killing, tender plants. Clear, calm skies and falling afternoon temperatures are usually the perfect conditions for frost. If the temperatures are falling fast under clear, windy skies-especially when the wind is out of the northwest-it may indicate the approach of a mass of polar air and a hard freeze. A hard or killing frost is based on movements of large, cold air masses. The result is below-freezing temperatures that generally kill all but the most cold-tolerant plants.
Cloudy skies: you may be in luck.
If the temperature is cool, but clouds are visible, your plants may be protected. During the day, the sun’s radiant heat warms the earth. After the sun sets, the heat radiates upward, which lowers the temperatures at or near the ground. However, if the night sky has clouds, these clouds will trap the heat and keep the warmer temperatures lower, closer to your plants, preventing a frost.
Wind also influences frost. If the air is still and windless, the coldest air settles to the ground. The temperature at plant level may be freezing, even though at eye level it isn’t. A gentle breeze, however, will prevent the cold air from settling and keep temperatures higher, protecting your plants. If the wind itself is below freezing, frost may be very damaging.
Humidity and moisture are good things when talking frost. When moisture condenses out of humid air, it releases enough heat to sometimes save your plants. When the air is dry, the moisture in the soil will evaporate. Evaporation requires heat, which removes warmth that could save your vegetables.
Location, location, location.
The location of your garden can have a tremendous influence on whether or not an early frost could wipe out your garden, but leave your neighbor’s alone. As a general rule, the temperature drops 3°F to 5°F with every 1,OOO-foot increase in altitude. The higher your garden, the colder the average air temperature and the more likely your plants will be hit by an early freeze.
However, lower isn’t always better. Cold air is heavier than warm air and tends to sink to the lowest areas, causing frost damage. The best location for an annual garden is on a gentle, south-facing slope that’s well heated by late-afternoon sun and protected from blustery north winds. A garden surrounded by buildings or trees or one near a body of water is also less likely to become frost covered.
The type of soil your garden is growing in also affects the amount of moisture it holds. Deep, loose, heavy, fertile soil releases more moisture into the surrounding air than thin, sandy, or nutrient-poor soil. The more humid the air is, the higher the dew point will be, and the less likely that frost will form on those plants. Heavily mulched plants are more likely to become frosted since the mulch prevents moisture and heat from escaping out of the soil and warming the surrounding air.
Know your plants.
The plant itself determines its likelihood of frost damage. Immature plants still sporting new growth into the fall are most susceptible-especially the new growth. Frost tolerance tends to be higher in plants with maroon or bronze leaves, because such leaves absorb and retain heat. Downy- or hairy-leaved plants also retain heat. Compact plants expose a smaller proportion of their leaves to cold and drying winds. By the same token, closely spaced plants protect each other.
Frost on its way?
If a frost is predicted, cover your plants, both to retain as much soil heat and moisture as possible and to protect them against strong winds, which can hasten drying and cooling. You can use newspapers, baskets, tarps, straw, and other materials to cover your plants. Cover the whole plant before sunset to trap any remaining heat. Be sure to anchor lightweight coverings to prevent them from blowing away.
Keep the soil moist by watering your plants the day a frost is predicted. Commercial fruit and vegetable growers leave sprinklers on all night to cover plants with water. As the water freezes, it releases heat, protecting the plants, even though they’re covered by ice. To prevent damage, the sprinklers need to run continuously as long as temperatures remain below freezing.
Cold Temperature’s Effects On Plants and Vegetation
FROST: Damage depends upon the length of frost duration.
LIGHT FREEZE: 29 degrees F to 32 degrees F / -2 degrees C to 0 degrees C. Tender plants killed with little destructive effect on other vegetation.
MODERATE FREEZE: 25 degrees F to 28 degrees F / -4 degrees C to -2 degrees C. Wide destruction on most vegetation with heavy damage to fruit blossoms and tender semi-hardy plants.
SEVERE FREEZE: 24 degrees F / -4 degrees C and colder. Heavy damage to most plants.
When is the average date for frost in your area? Check out our Average Frost dates here.
How to protect container plants and pots from winter frost
Plants love to grow in pots during summer, but they are exposed to the elements in winter. In the soil, roots are protected by the warmth of the earth. But in pots they are vulnerable to frost, snow and cold winds.
Patio pots are also prone to waterlogging in times of heavy rain, which can kill plants. Sodden soil has all the air pushed out of it by the water, meaning roots can’t access any oxygen.
As if that’s not enough, cold temperatures can also cause pots to flake and crack, damaging or killing the plant in the process.
So here is how to make sure all your container plants, and pots, survive the winter weather.
Move tender plants
Plants that are not winter hardy simply need moving to a frost-free location. A cool greenhouse, porch or conservatory is ideal. Large, established specimens can be placed in a sheltered spot against the wall of the house, which should be warmer.
How can I stop pots cracking in frost?
Damaged pots in winter cost you twice – once to replace the pot and again to replace the plant.
There are two options for winter patio pots: frost-resistant, which is tough but may crack or flake in frost, and frost-proof, which should survive it. Generally, glazed ceramic pots survive the cold much better than unglazed terracotta.
But no pot will survive if the compost is waterlogged. Water expands when it freezes, meaning that wet compost will eventually crack the pot.
Even if you choose frost-proof containers, do not allow the compost to become waterlogged.
Protect pots from frost by moving them against the house, where the temperatures will be warmer. You can also wrap them in insulation or move them into an unheated greenhouse or shed when very cold temperatures are expected.
Winter Container Gardening
Winter is an especially good season to explore the many pleasures of foliage in your garden planters – color, texture and lots of personality.
Planters must be chosen carefully for winter hardiness—clay, ceramic and terracotta planters are not recommended as they tend to crack following frost or freezing. Metal planters can retain the cold more than other materials. Resin, fiberglass, plastic and wood are good choices for a winter container garden.
Container Gardening through the Winter
- Since the planter raises the plant above ground there isn’t any soil blanket to insulate the roots of the plant. It is recommended that plants placed in containers be two zones lower in cold hardiness than the hardiness zone they are to be grown in.
- Slow-growing evergreens can be excellent choices for medium to large garden planters to provide greenery through the winter. Some examples are: Colorado Blue Spruce, Alberta Spruce, Weeping Norway Spruce, Umbrella Pine, Siberian Cypress, Arborvitae and Juniper.
- To help compensate for the moisture stress factor try ‘Soil Moist’…these granules absorb irrigation water and gradually release it as it is needed by the plant.
- Water only in winter when soil is unfrozen and approaching dryness. As winter sets in and the potting medium freezes, you must cease watering.
- In very wet regions, consider using ‘pot feet’ of either terra cotta or cast stone. They elevate the planter allowing it to dry out. This will eliminate or lessen the staining of surfaces by water draining from the planter and pooling at the base.
- The larger the planter, the greater insulation of the potting soil around the plants’ roots. This increases your chances of success and reduces stress on the plants’ roots.
- To extend your large planter display through to the spring, plant spring-flowering bulbs to the recommended depth before adding the other plants.
- Put trailing plants at the edge of the container, remember that plants grow more slowly in winter than summer, so pack them in fairly closely.
- During particularly cold or wet periods, move smaller planters close to buildings for added protection.
Many hardy perennials and ornamental grasses will survive just fine outdoors, or in an unheated space, as long as they are protected from severe cold. The issues facing plants that are left outside through the winter are:
- frost damaging leaves and tender shoots
- a hard freeze killing the entire plant
- freeze/thaw action of soil disturbing the roots or cracking the container
- the weight of snow or ice breaking the plant
Be sure to carefully consider each of these issues when deciding on how to over-winter your planters. The goal of overwintering most hardy perennials is to prevent them from getting too cold—not to keep them warm. A good winter temperature range for most plants is between 32-45F.
The most common approach for protecting plants outside is to wrap your pots with some kind of hay and burlap to insulate them. But if hay is too messy, there are lots of other things you can use: leaves, blankets, bubble wrap, or styrofoam packing peanuts. Any insulating material will work well.
To protect the top part of the plant from frost, place several tall stakes around the rim of the pot and wrap with plastic or cloth. Bubble-wrap is excellent for wrapping around your planters for insulation. If you can move your pots, take advantage of any heat or wind protection close to your house or other out-buildings. Grouping all of your garden planters in one place can make it easier to construct a protective shelter to protect them from strong winds or heavy snow.
Bubble wrap for insulation from heat
If it’s clear, it will likely worsen the problem. Light will pass through. When it hits the pot, it will be turned to heat and be conducted through the pot material and into the soil, partially because the insulating wrap traps is there. If there was no wrap, the light would still turn to heat when it hits the pot, but the heat would not be trapped and would dissipate into the air. You would be better served to double pot and fill the space between the pots with something well-aerated (gravel, e.g.) and keep it moist during the heat of the day. Painting your pots white or selecting light colored containers can make as much as 40* (or more) difference in soil temps too, so choose light colored pots if possible. Wrapping them with a white material or tin foil (I know – classy, huh) is effective, too.
Most people don’t realize that for most plants, just a few degrees difference in soil temperatures can have a very big impact on growth. I was just reading up on peach trees & discovered that best growth occurs at soil temps between 65-70*, with growth reduced by about 40% at 75* and 97% at 80*. Roses showed a similar pattern, but actually at temperatures even lower than the peach trees. For best vitality, we should try to always keep container soil temperatures below 80* whenever we can.
Wrapping Plants In Burlap: How To Use Burlap For Protecting Plants
Wrapping plants with burlap is a relatively simple way to protect the plants from winter frost, snow and ice. Read on to learn more.
Burlap Plant Protection
Covering plants with burlap can also protect plants from winter burn, a damaging condition caused by a combination of winter sunlight and depleted soil moisture. Burlap is more effective than plastic because it allows the plant to breathe so air circulates and heat isn’t trapped.
Burlap for protecting plants can be as simple as an old burlap bag. If you don’t have access to burlap bags, you can purchase sheet burlap by the yard at most fabric stores.
Covering Plants with Burlap
To cover a plant with burlap, begin by placing three or four wooden or stakes around the plant, allowing a few inches of space between the stakes and the plant. Drape a double layer of burlap over the stakes and secure the material to the stakes with staples. Most experts recommend that you not allow the burlap to touch the foliage if you can help it. Although not as worrisome as plastic, if burlap becomes wet and freezes, it can still possibly damage the plant.
In a pinch, however, it shouldn’t harm the plant to wrap in burlap or drape over the plant directly if cold, dry weather is imminent. Remove the burlap as soon as the weather moderates, but leave the stakes in place so you can cover the plant quickly in the event of another cold snap. Remove the stakes in spring when you’re sure freezing weather has passed.
What Plants Need Burlap?
Not all plants require protection during the winter. If your climate is mild or if winter weather includes only occasional light frost, your plants may need no protection other than a layer of mulch. However, burlap is handy to have around in the event of an unexpected dip in temperatures.
The need for protection also depends on the type of plant. For example, many perennials are hardy in winter, but even hardy plants may be damaged if they aren’t healthy or if they are planted in soggy, poorly drained soil.
Often, newly planted shrubs and trees benefit from protection for the first one to three winters, but are winter-tolerant once they are well established. Broadleaf evergreen shrubs such as azaleas, camellias, rhododendrons often require covering during extreme cold.
Potted plants, which are more susceptible to cold, may need several layers of burlap to protect the roots.
How to Winterize Shrubs
Photo by Richard Warren
Evergreen shrubs can withstand flurries, but heavy snow and other hazards of the upcoming season can wreak havoc on these workhorse yard plantings. This Old House landscape contractor Roger Cook shares these late-November prep tips to show you how to protect your shrubs in winter so they make it to spring damage-free.
Photo by Richard Warren
Shrubs that were planted less than six months ago can get dried out by strong gusts. Shield them by hammering 1x stakes into the ground to make a frame, then wrap with burlap and staple the material to the stakes.
Snow and Ice Protection
Photo by Richard Warren
Wrap tall, narrow shrubs into a tight column with twine to keep branches from collecting heavy snow or ice and breaking off.
Shelter plants up against your home from falling icicles and snow melt with a simple, reusable A-frame structure that you can make from 2x4s and exterior-grade plywood.
Photo by Richard Warren
Road deicer can dehydrate your bushes. Keep it off curbside greenery with a barrier made from 2×4 stakes and erosion-control fabric—the fine mesh won’t let salt seep through.
Photo by Richard Warren
Repeated freezing and thawing can uproot shrubs that are newly planted or establish roots slowly. Moderate the soil’s temperature by adding a 2- to 4-inch layer of mulch around the base of shrubs.
How do I protect my trees and shrubs from winter damage?
Last winter was remarkably tough on many landscape plants. Rhododendrons were especially hard hit, as well as numerous other evergreen and deciduous trees and shrubs. While it is impossible to entirely prevent plant injury from severe winter weather conditions, there are a number of practices gardeners can employ to help keep their trees and shrubs healthy.
Proper care during the growing season and right up through the fall is a crucial part of keeping evergreens alive through the winter. Providing adequate water is essential to keep plants from suffering from stress, as healthy plants are much better prepared to survive the winter. For optimum growth, most woody plants require one inch of rainfall or supplemental irrigation every week. In the fall, when the air temperature drops below that of the soil, shoot growth ceases and roots continue to develop until the soil dips below 40℉. In order to encourage maximum root development, and by extension improve winter hardiness, water thoroughly and consistently, applying enough water to moisten the soil to a depth of eight to ten inches at least once a week, continuing until freezing temperatures arrive.
Wrapping with Burlap and Making Windbreaks
Broadleaf evergreens, such as Rhododendrons, are particularly susceptible to drying out in the winter months. Even in cold weather, leaves and needles lose water in a process called transpiration. Water loss is greatest during periods of strong winds and mild sunny weather. In super cold temperatures, the ground freezes and cuts off the water supply to the plant’s roots. When water is transpired faster than it is taken up, the leaves begin to desiccate and turn brown.
Desiccation can be mitigated by erecting windbreaks made from burlap or canvas attached to frames around the plants. These barriers should be placed on the side of the prevailing winds. Some plants such as arborvitae have growth habits which lend themselves to a complete wrapping of burlap. If wrapping plants, never use black plastic as it causes extreme temperature fluctuations. Wrapping with burlap and building windbreaks isn’t always enough to prevent winter injury, but it can help. If nothing else, plants wrapped with burlap are less likely to be browsed by deer.
Gardeners frequently ask whether anti-dessicant sprays should be used to protect evergreens from winter damage. There is evidence that anti-dessicants can be helpful when applied correctly but they can be ineffective or even damaging when used inappropriately. For best results, make sure to read and follow all instructions on the product label. Most anti-desiccants are best applied when temperatures are around 40-50 degrees. Within this temperature range, the spray should have good coverage on the foliage. Because plants lose water through both the upper and lower surfaces of their leaves, all parts of the plant should be sprayed. Make sure not to apply too early. Spraying anti-dessicants before plants are dormant increases potential for damage, because the spray can trap excess water in leaves, which can freeze and cause cells to rupture. Wait to apply until evergreens are fully dormant in the late fall.
Mulching to Protect Roots
Perhaps surprisingly, snowy winters are often best for tree and shrub survival. Snow cover insulates the soil and helps prevent it from reaching a killing temperature, and it limits freezing and thawing. Thus, woody plants are more likely to suffer cold damage in winters where there is very little snow to protect their root systems. Since there is no guarantee of adequate snow cover, mulching trees and shrubs (especially those that have been newly planted) becomes very important. Aim to apply at least two inches of woodchips or straw over the root zone, taking care not to pile mulch against trunks. Extra mulch can be removed in the spring once the ground begins to thaw. When available, cut evergreen boughs can also provide good insulation.
Preventing Deer Damage
Throughout much of New Hampshire, white-tailed deer have become a major garden and landscape pest. When food is scarce in winter months, deer will heavily browse on some evergreen plants, including arborvitae (Thuja occidentalis) and yew (Taxus sp.). Installing fencing around plants susceptible to deer is the most effective method of protection, but it can be quite expensive and impractical in some landscapes. Many repellants are also available on the market with mixed degrees of effectiveness. In general, repellents that trigger a fear response are most effective. These products generally contain putrescent egg solids, predator urine or slaughterhouse wastes, and they may not be appropriate for use near heavily-trafficked walkways or buildings. Alternatively, you can place area repellents near affected plants, such as bar soap or garlic “sticks.” These repellents are usually clipped or hung from the branches of trees and shrubs that deer enjoy. If deer are only an occasional issue in your garden, you may find that they provide enough protection. Even in the best of circumstances, repellents will never completely eliminate deer damage, but they can help reduce it. For best results, make sure to apply repellents according to the product label.
Note that all deer-proofing methods work best when they are employed early in the season. Start applying repellents in the mid-to-late fall to discourage deer from making regular visits to your landscape.
Plant Selection and Planting Location
Even when you do everything you can to protect plants, winter damage is still a possibility. Some plants are simply better adapted to survive than others. Many winter injury issues can be solved by choosing appropriate plants, and hardiness is the first thing to consider. Trees and shrubs should be hardy enough to survive in the zone where they are planted without too much extra care. In most of New Hampshire, this means selecting plants which are hardy in Zones 3-5.
Another thing to keep in mind is planting trees and shrubs in the proper place in the landscape. Winter winds and sun can be extremely damaging to evergreens so they should be planted in protected spots out of the prevailing winds. Broadleaf evergreens in particular should be planted on the north, northeast, or eastern sides of buildings, or behind barriers where they are protected from the elements.
Broadleaf trees that have thin bark, like maples and cherries, are susceptible to frost cracking. This type of injury occurs on the southwest side of trees on sunny days in the winter when the sun warms the bark enough for the sap to flow. When the temperature drops quickly, the bark contracts and splits vertically. Sunscald can also occur when the temperature drops suddenly. Cells that have become active on the sunny side of plants are killed, resulting in dead, sunken areas. If planting a tree with thin bark, try to place it in a location where it will receive some protection from winter sun instead of in the open landscape. Even consider placing smaller shrubs near the base that will shade the south side of the tree and reduce the likelihood of frost cracking.
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