- How to feed your tree?
- Natorp’s tree nursery grows 30,000 trees each year. Our experts share their tips on feeding for the best growth.
- Welcome To East River Nursery
- The Benefits of Deep-Feeding Trees
- The 6 Best Fertilizers for Trees and Shrubs
- Best Fertilizer for Shrubs and Trees Reviews
- 1. Jobe’s 01310 1310 Fertilizer
- 2. Miracle-Gro 1001233 All Purpose Plant Food
- 3. Miracle-Gro 3002410 Shake ‘N Feed Flowering Trees and Shrubs
- 4. Ross 14636 Root Feeder Refills
- 5. Osmocote 274850 Plus Outdoor and Indoor Smart-Release Food
- 6. Scotts Continuous Release Evergreen Flowering Tree and Shrub Fertilizer
- What is the Best Fertilizer for Trees and Shrubs?
- When is the Best Time to Fertilize Trees and Shrubs?
- How to Fertilize Trees and Shrubs?
- How Often Should You Fertilize Trees and Shrubs?
- How to fertilize trees, shrubs, flowers and fruits
- Fertilizing Trees and Shrubs
- Soil pH
- What to use?
- Rates of application
- Methods of application
- Frequency of application
- Time of application
- Fertilizing Trees & Shrubs
- Deep Root Feeding Trees and Shrubs
- Which Trees and Shrubs Should Be Fertilized?
How to feed your tree?
When should you feed?
Spring and mid to late fall are excellent times for feeding. If you’d like to do it yourself, here are the ways we recommend:
For new trees, use a root stimulant such as Bonide’s Plant Starter or Espoma’s Bio-tone. Both are light and easy feed for new trees and help promote early strong root development. Plant Starter is mixed with water and poured at the base of the tree. Bio-tone is added to the soil when backfilling around the tree.
Planted 1-2 years
For trees planted 1-2 years, we recommend using a water-soluble fertilizer such as Bonide’s Plant Starter or Miracle-Gro, pouring the mixture around the base of the tree. The Ross Root Feeder is another option for water-soluble fertilizing. It’s a unique tool (attaches to your garden hose) that injects the water-soluble fertilizer right into the soil, as well as helping in light soil aeration. Also, this can be used as a watering tool without adding the fertilizer!
Planted 3 or more years
Fertilizing your lawn regularly with a lawn food helps to feed your existing trees.
Ross Root Feeders are an easy way to feed larger trees injecting a water-soluble fertilizer into the soil/root zone, as well as watering the tree and lightly aerating the soil. This is the same process professionals use to feed established and mature trees. Again, this tool is also an excellent way to water trees during periods of drought!
The Importance of Vertical Mulching
Vertical mulching is an excellent way to not only core aerate the soil around trees, but it can also be used to feed. Vertical mulching is the process of drilling a series of 2-inch diameter holes approximately 8 to 12 inches into the ground. These holes are drilled about 18-24 inches apart in a circular pattern, starting 6 feet or so away from the tree’s trunk, working your way out (circular pattern) to several feet past the drip line of the tree. The holes can be left open or backfilled with coarse products like sand, pea gravel, turface, or compost, followed by a good watering. This process opens up the soil around the tree for better airflow, better water absorption into the soil/root zone, and creating better areas for the roots to grow.
Vertical mulching can be used as a means of fertilizing the tree by adding a granular fertilizer to the backfill used to fill the open cores drilled around the tree. This also is an opportunity to apply soil amendments such as soil sulfur and Ironite for chlorotic trees. This is an excellent way to feed and helps improve the flow of air and water into the soil. It is time and labor-intensive, and maybe one to consider having a professional do for you!
Calculating the Amount of Fertilizer to Apply with Vertical Mulching:
If using Espoma’s Tree-tone, Plant-tone, or Milorganite, read the label for amounts needed. Then, distribute the amount evenly into all the cored holes.
If using a fertilizer such as 10-10-10, look for a tree feeding rate on the bag. If nothing is available, then calculate using 1 pound per inch diameter, for tree trunks 1-6 inches in diameter. For those tree trunks 6 inches diameter or larger, use 3 pounds per inch diameter. Once finished, be sure to water with good soil soaking.
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Even the most novice gardener knows the importance of providing proper feeding and fertilization to a new flowerbed, young vegetable seedlings or even recently planted turf, but many people don’t realize that new trees also need good feeding for strong, healthy growth. Fortunately, there are many organic ways to feed your trees so they can become well established and will resist stress, repel insects and be less susceptible to diseases.
- Compost: Compost is the easiest and most common way of organically feeding trees. Compost can be gently mixed with soil in the hole as a new tree is planted for instant nourishment, and adding compost mixed with mulch around the base of the tree will provide ongoing nutrients for the hungry tree.
- Manure: If a ready source of manure is available – ask a local farmer, they generally have plenty to share! – it can be great for feeding trees. Mix the manure with compost or mulch, or add it around the tree’s base to gradually decay and provide abundant nutrition for the tree’s growth and health.
- Leaf Litter: Instead of raking up every leaf in the fall, leave a layer of fallen leaves, pine needles and other natural debris under the tree for nourishment. If the debris is too thick, run it through a mulcher or mow over the fallen leaves to trim them into smaller, more quickly decaying pieces.
- Remove Turf: Be sure every bite of organic food and fertilizer is nourishing the tree by removing turf around the base so the grass does not absorb the nutrients first. Ideally, turf should be removed to the drip line of the tree – the widest extent of the bottom branches – but if that is too big an area, any ring of bare soil will help. Cover the soil with wood chips or other mulch to conserve moisture and provide further nourishment.
- Water Well: A dehydrated tree will be a sickly tree, and it is important to water trees well so they can more thoroughly absorb nutrients from feeding, and the water will leach nutrients to the roots, bringing even more nutrition to the plant. Ideally, water trees at ground level, thoroughly soaking the roots for good watering that will encourage healthy growth.
- Bird Feeders: Hanging a bird feeder or two in a tree is a simple way to organically feed the tree. Bird feces will fall onto the soil below the feeders, and debris from the feeder will also drop and decay into essential nutrients for the tree to absorb.
- Proper Pruning: Properly pruning a tree will avoid any wasted nutrition. Dead, damaged or diseased branches should be removed right away, and every tree should be pruned occasionally to increase air circulation and sunlight penetration in its foliage. This will help the tree best metabolize the nutrition it absorbs.
- Organic Fertilizers: Many companies offer organic supplemental fertilizers that can be used for feeding trees. For the best option, the soil should be tested before adding any fertilizer to be sure the proper mix of nutrients will be offered to the tree, and because these fertilizers are concentrated, it is critical to follow the application instructions to avoid damaging the tree or unbalancing the soil.
With so many ways to feed trees organically, it’s easy to be sure every tree is getting adequate nutrition for proper growth, strong foliage and a long, healthy life.
The Benefits of Deep-Feeding Trees
Q: “After losing an old pine tree in my front yard, I’m determined to save its twin, which provides wonderful shade. One arborist says it needs “deep feeding,” at a cost of $1,000. Another says a tree this old doesn’t need such a treatment. What should I do?”
—Syndia Marxer, Chandler, Ariz.
A: I believe that a tree in distress, no matter how old, can benefit from deep feeding: having fertilizer injected through a needle about 6 to 18 inches into the ground, beyond the reach of greedy grass roots. But if your tree is healthy and pushing out plenty of needles every spring—it certainly looks to be in good shape in the photo—then deep feeding probably isn’t necessary.
That said, your tree may benefit from some extra attention to its root system because trees in streetside locations are vulnerable to all sorts of stresses, such as heat, drought, car exhaust, and the like.
First, test the soil to find out exactly which minerals, if any, are lacking. Then, if fertilizer is needed, spread it in early spring or early fall after removing any grass or mulch around the tree. At the same time, top-dress the area with 1 to 2 inches of compost, and work it into the soil with a rake. Compost encourages the growth of beneficial mycorrhizae, soil fungi that enhance the ability of roots to absorb nutrients. Finally, cover the soil with mulch, keeping it 3 inches from the trunk.
Gardening is a hobby that takes a lot of time and patience to be successful. You only see the fruits of your labor after lots of hard work, literally!
Even with the right amount of rain and sunshine, some plants need a little extra push to grow correctly.
Others may grow alright but definitely have room for improvement and increasing blooms. In these cases, most gardeners resort to using fertilizers.
Finding the best fertilizer for trees and shrubs requires some research. This article gives some insight into the top fertilizers, so you can choose the best one for you.
The 6 Best Fertilizers for Trees and Shrubs
There are a few things you should keep in mind before getting your hands dirty with fertilizers. Most importantly, think about your growth goals. This chart compares the six best fertilizers, so you have good starting points to test out.
|Jobe’s 01310 1310 Fertilizer||16-4-4
|Miracle-Gro 1001233 All Purpose Plant Food||24-8-16|
|Miracle-Gro 3002410 Shake ‘N Feed Flowering Trees and Shrubs||18-6-12|
|Ross 14636 Root Feeder Refills||25-10-10|
|Osmocote 274850 Plus Outdoor and Indoor Smart-Release Food||15-9-12|
|Scotts Continuous Release Evergreen Flowering Tree and Shrub Fertilizer||11-7-7|
Best Fertilizer for Shrubs and Trees Reviews
1. Jobe’s 01310 1310 Fertilizer
Different fertilizers come with different features. First up is the Jobe’s brand. This particular product comes in a spike form.
Fertilizers like these are easy to apply to the soil because of their shape. All you have to do is make a little space in the ground by taking out some soil. Then, insert the fertilizer stick where needed, and cover it again.
Jobe’s fertilizer sticks come in a few different variations depending on the plant. You can choose from fruit and citrus, tree and shrub, and evergreen varieties based on your garden.
There is also room to customize how many spikes you want to buy with options from 5-160 spikes.
When using this product, it’s good to know that these spikes work in a slow-release format. If you apply it at the beginning of the season, they’re going to last all the way to the end of it. This makes for an efficient and non-wasteful fertilizer.
When applying these fertilizer sticks, make sure to apply them once at the start of spring. You can then reapply towards the end of fall. This ensures a nice fertilizer spread throughout the growing season.
2. Miracle-Gro 1001233 All Purpose Plant Food
Next, we have the tried and true Miracle-Gro all-purpose plant food. Miracle-Gro is truly a miracle in terms of delivering results, so this is a solid product to test out. It’s also very easy to use.
When it comes to using the Miracle-Gro plant food, all you have to do is shake it onto the area that needs fertilizer. After that, make sure to water the plants and ground to allow for proper dispersion.
Alternatively, you can add the Miracle-Gro plant food directly into your watering can. Give it a good mix, and then water your plants as you normally would. This saves you time from having to complete two separate steps.
Using the Miracle-Gro plant food is simple if a bit time-consuming. Unlike the fertilizer spikes that release over time, this needs to be reapplied on a weekly basis. You might be able to apply it twice a week, but that depends on your growth goals.
An added bonus of using this Miracle-Gro product is that it’s safe for all plants. You don’t have to buy a separate product for each. Miracle-Gro claims that it doesn’t burn any plants with the correct usage, so that’s a great promise.
3. Miracle-Gro 3002410 Shake ‘N Feed Flowering Trees and Shrubs
If you’re looking for a Miracle-Gro product that has the benefit of extended-release, this one is for you. Consider Miracle-Gro’s Shake-N-Feed plant food. This combines the excellent formula of Miracle-Gro with a patented longer-lasting design.
Miracle-Gro’s Shake-N-Feed plant food comes in many different variations. You can choose from rose, vegetable, palm, weed preventing, and all-purpose formulas. This product can also be used on both planted and potted flowers.
A great feature that this product comes with is the extended-release formula. You can apply some plant food at the beginning of the season and enjoy its benefits for the next three months. This can be used to help both the bloom growth and the root and stem strength of your garden.
Ingredients like kelp, bone meal and earthworm castings are all very nutritious. When combined, they make the perfect formula to keep your plants thriving year-round.
Unlike the other Miracle-Gro product, this one doesn’t need any watering for application. Simply shake the mixture onto the desired areas, and pat it down gently. That should take care of your plants for the next three months!
4. Ross 14636 Root Feeder Refills
This next product comes with both fertilizer and a fertilizer applicator in one. The Ross root feeder refills are easy to install. Many customers also gave glowing reviews for this product.
One of the best things about the Ross root feeder refills is the design of the applicator. The design for this product is very sturdy, and it’s built to last the wear and tear of gardening. The tough plastic of the feeder head keeps its shape throughout irrigation.
The process of applying the feeder is a bit different from other fertilizers. It works like other fertilizer sticks do, except for one main part. You have to add the fertilizer into the head before you stick it in the ground.
This comes with refills, so you simply add a stick or two of the refill fertilizer. Close the top of the head, and insert it into the ground. Because this is plastic, make sure you have ample room in the ground for it, so you don’t use force.
Next, add a little bit of water to help the fertilizer dissolve. It’s going to take a few minutes to fully dissipate. Because the head is inserted in the ground, it ensures the roots get an even application of the product.
5. Osmocote 274850 Plus Outdoor and Indoor Smart-Release Food
Next is the Osmocote smart-release plant food. This product may not be as well-known as some of the others on the list, but it is right up there with the best. It has several positive features to its name.
One of the main specialties for the Osmocote plant food is that it feeds the plants for six months. That is one of the longest extended-release periods for fertilizers on this list. If you’re looking for a product that lasts, this one is perfect for you.
Secondly, Osmocote plant food can be used for both outdoor and indoor plants. Whether you’ve planted them in the ground or in a pot, this product can help them grow stronger and longer.
There’s also no differentiation on which plants you can and can’t use this on, so everything goes.
The Osmocote smart-release plant food is successful because it’s fortified with 11 nutrients. The quality of these ingredients means that the plants and shrubs also experience it.
As the icing on the cake, this product is available at an affordable price. It is right along the line when it comes to comparing prices. It’s not too expensive or too cheap, but just right.
6. Scotts Continuous Release Evergreen Flowering Tree and Shrub Fertilizer
Last but not least is the Scotts continuous release fertilizer. Like the other products on this list, this one also has several pros for using it. Let’s start with the most important: the ingredients.
The ingredients included for this product are great for helping different plants grow. However, one major component is missing: iron. Iron helps to reduce yellowness in the leaves, and without it, a big portion of good fertilizer is missing.
Aside from that point, this Scotts continuous release fertilizer has a lot to offer. This product is great because it releases throughout the soil over several months. You can apply it at the beginning of the growing season and see results all season long.
This fertilizer is perfect for acid-loving plants like evergreens, magnolias, dogwoods, and hydrangeas. It also works really well with azaleas, camellias, and rhododendrons. It’s successful with a wide range of plants because it encourages growth at the root.
Lastly, you have a few different options when it comes to package size with this product. You can opt for a smaller 2-pack at a reasonable price. You can also buy a 3-pack product that’s available for a discounted price.
What is the Best Fertilizer for Trees and Shrubs?
Many people think that fertilizer is a cure-all for all types of plant problems, but this is far from the truth. They think that fertilizers work with any plant to produce substantial results. But there is a time and place for every fertilizer, not a single fertilizer for every time and place.
Before you even look for the best fertilizer, first determine the type of fertilizer you need. The first test you should do is a regular soil test. This can tell you about the alkalinity or acidity of your soil, and then you can figure out how to balance that pH out.
Another thing that lets you know if you need fertilizer is the appearance of your plants. If you notice yellow leaves, little twig growth, and low nutrients, you need fertilizer.
You need to solve underlying problems, like disease-ridden plants and excessive insects. It’s important to take care of these basic problems first before adding fertilizer. Fertilizer doesn’t work if the plants aren’t at their best stage to grow.
Now that you’ve determined a need for your fertilizer, let’s take a look at your options in terms of types. Opt for a complete fertilizer, like a 16-4-8, 12-6-6, or 12-4-8, unless your soil’s phosphorus and potassium levels are optimal. Then, take a look at the release designs.
Fertilizers are either fast-release or extended-release products. Fast-release designs are meant to absorb in your soil in just a few minutes. On the other hand, extended-release products take their time in spreading out.
Fast-release fertilizers work quickly, but they sometimes leach the natural soil. This leaves it with fewer nutrients than before, but not enough to cause lots of damage. This fertilizer works better with sandy and well-drained soils.
Slow-release fertilizers have their own issues. Naturally, they take longer to get into effect. But, these fertilizers are great for new plants because they have a smaller chance of “burning”.
Fast-release fertilizers work great for established plants that need a quick pick up. Slow-released products work great for building up new plants. It all depends on what growth stage your plants are at.
You might be wondering about natural fertilizers, like cow manure or composted materials. These fertilizers are excellent because they contain small amounts of iron and zinc. These chemicals aren’t found in synthetic fertilizers.
Natural fertilizers don’t have a concentration of nitrogen, phosphorus, and potassium. That means you have to use more of them to get the same effect as synthetic fertilizers. You can see how there are pros and cons to both synthetic and natural products.
Once you figure out the formula and type of fertilizer, think about the extra features you want it to have. Synthetic fertilizers can also act as repellents for weeds. You can buy fertilizer with special features by reading the labels closely.
It helps to make a list of what you learn about your soil and plants. Then, you can find fertilizer to tackle the different problem areas you have. After that, wait for nature to run its course with your fertilizer in action.
When is the Best Time to Fertilize Trees and Shrubs?
It’s important to remember that there are certain times that fertilizers work best. If your plant is dying of thirst, it just won’t grow, regardless of how much fertilizer you throw on it.
Keeping a log of your planting times can help you find the best time to apply fertilizer for maximum growth.
You’re looking for a time when the roots of the plants are actively growing. Pay attention to the changes your plants make, and then add fertilizer accordingly. It also helps if you research the growth patterns of your plants beforehand.
As a general rule, it’s best to apply fertilizer to plants in the early spring. This helps them get ready for their upcoming growth period. You can also give a light helping of fertilizer in the early summertime.
Be careful when you fertilize any time before or during summer. If the weather conditions are too hot and dry, your plant isn’t going to absorb the fertilizer. Ensure that it’s properly watered and healthy before adding additional nutrients.
You should also be sure to apply fertilizer at a time when you have adequate water or irrigation methods. If you’re going through a drought, forget the fertilizer altogether. Applying fertilizer when plants need it and can absorb it ensures good results.
Tree and Shrub Fertilizing Time Video Guide
How to Fertilize Trees and Shrubs?
Now that you’re ready to fertilize your trees and shrubs, just how do you do it?
There are a few different methods of fertilization. Let’s start with direct and indirect fertilization.
Indirect fertilization is when your plants and shrubs are fertilized through runoff. You may have fertilized your lawn recently, and the leftover nutrients have traveled. In this case, you don’t have to do much to fertilize.
Direct fertilization is obviously a more active form of fertilizing your plants. You’re applying the fertilizer directly to the plants and shrubs that need it. This type of fertilization also has different methods to get it done.
One of the best ways to fertilize directly is by using a broadcasting system. You can cover much more ground by having an object spread the fertilizer from a high point. It’s like how you salt much more food if you hold your hand higher above the dish than if you bring it close.
Using a drop-type spreader, you can evenly spread a good amount of fertilizer over your plants. You should do this by distributing half of the product on the lawn in one go. Spread it in a perpendicular manner to what you did initially the second time to get good coverage.
If you’re fertilizing shrubs with lots of leaves, make sure to use a leaf rake to help bring that product down. Leaving excessive amounts of fertilizer on the leaves can cause damage and burning. You can also just add fertilizer directly onto the ground near the roots to avoid this.
A common way to distribute fertilizer is in a liquid form. This can be done in two ways. The first way includes a few attachments.
You attach your fertilizer solution to your garden hose and spray directly on the plants. Usually, this solution is less concentrated, so the chances of burning are smaller. This method helps dissolve nutrients beforehand, making for a speedy absorption.
The second way you can apply fertilizer with water is by adding it to the irrigation system. This works similarly to the broadcasting method. First, start by adding a small amount of fertilizer to your irrigation head.
Make sure to keep a steady hand here, as too much fertilizer, even when diluted, can harm your plants. When you turn on your water, the system begins dissolving the fertilizer immediately. This is then added to the soil and leaves of your plants, effectively coating them.
Last but not least, you can use the spike method to fertilize. Fertilizer spikes are a great way to get a slow-release product into your soil. It also helps reach the roots of the plants because the spikes are underground.
Whichever fertilization method you use, remember that you always need a little water. This helps dissolve the fertilizer and nutrients to get the magic started. Without water, some of the nutrients evaporate into the air without benefiting anything.
How Often Should You Fertilize Trees and Shrubs?
How often you fertilize your plants depends on their age and the season. Although there is no set amount of fertilizer you should give your plants, there is a general rule of thumb. Younger plants often require more fertilizer to get strong.
Depending on the fertilizer type, you may have to fertilize once every two or three weeks. If you have an extended-release fertilizer, apply it according to its directions. This helps keep your plants safe from fertilizer burns.
There are also two times in the year when it’s generally always a good idea to fertilize. Early spring and autumn are the best times to lay down some good foundations. Fertilizing during these times helps strengthen your plants for growing and dormant seasons.
If you’re still unsure of how to fertilize your plants, ask your local plant nursery worker. They’re skilled in helping plants grow and know them like the back of their hand. So, they can point out the best tree and shrub fertilizer for your plants and area.
Don’t feel discouraged if a particular fertilizer doesn’t seem to be working. Remember, these products work from the root up. Building a good base is key, and with the right fertilizer, your plants are going to be the base of a healthy garden.
8 Best Fertilizer for Strawberries – (2020 Reviews & Guide)
10 Best Fertilizer for Indoor Plants – (2020 Reviews & Guide)
The 6 Best Fertilizer for Blueberries – (2020 Reviews & Guide)
How to fertilize trees, shrubs, flowers and fruits
Lawn fertilizing is comparatively easy, as you measure the lawn area and apply at the rate on the label. But fertilizing trees, shrubs, vines, fruits, perennials and annuals is often less clear-cut. Let’s examine the guidelines for non-lawn plants.
• Plants need nutrition like humans need food, and the three elements required in greatest quantity are nitrogen, phosphorus and potassium, which are the three primary numbers listed on every fertilizer label.
• Lawn fertilizers are high in nitrogen, the first number in an analysis like 30-5-5, to promote green, leafy growth.
• Trees, shrubs, perennial flowers, annual flowers, fruits and vegetables require a more “well-balanced” or “complete” fertilizer, in which the three main nutrients are closer in proportion, such as 10-10-10, which provides nitrogen for green, healthy foliage and phosphorus and potassium for flowering, fruiting and root development.
• Although many fertilizers are specially packaged for plants like roses, tomatoes or trees, an all-purpose, well-balanced fertilizer like 10-10-10 is effective, eliminating the need for many individual types.
• Dry granular fertilizers or water-soluble Miracle-Gro types are both beneficial.
• Soils in the Upper Midwest are generally considered fertile. Adding fertilizer can boost growth and production, helping plants reach their maximum.
• Fertilizer isn’t medicine for sick plants. Force-feeding a declining plant can make matters worse. Fertilizer turns an OK plant into a more prolific plant.
• For best results, soil testing of gardens and yards can provide a baseline to determine present fertility and recommend additions. North Dakota State University and the University of Minnesota both have soil-testing labs.
• Don’t fertilize during dry periods. Plants can’t use fertilizer without adequate moisture. Fertilize before a rain, or water after application.
• Organic fertilizers are derived from plant or animal sources. Manure, compost and other organics are usually lower in fertilizer analysis with nutrients released slower but are longer-lasting, plus they enrich soil tilth.
• Inorganic or chemical fertilizers are derived from minerals or manufactured products. They react faster than most organics and are higher in analysis, but dissipate quicker and they generally don’t improve soil tilth.
• Both organic material and inorganic fertilizer can be combined effectively, if desired.
• Apply fertilizer to trees, shrubs, fruits and perennials when spring’s flush of rapid growth begins, and then monthly through June.
• July 4 is the cutoff date for fertilizing trees, shrubs, fruits and perennial flowers. Fertilizing later stimulates growth that might not have sufficient time to toughen or harden off before winter.
• Fertilizer is especially effective on younger trees, shrubs, fruits and perennials. Older, large, established plants usually grow fine without fertilizer additions.
• Starter fertilizers help vegetable and flower transplants establish quicker.
• If in doubt about quantity, always err on the low side, as too much can burn plants. Follow the label.
• Granular fertilizer is best cultivated shallowly into the soil surface after application and watered in.
• Fertilizer spikes provide nutrition, but materials don’t move laterally a great distance, limiting spikes’ efficiency.
• For vegetable gardens, fertilizer can be broadcast and tilled in before planting, or side-dressed in bands beside rows or in a circle around individuals. Follow label directions, which for 10-10-10 is about 2 cups (1 pound) per 100 square feet or about a half cup per 10 running feet of row.
• For trees, apply 1 cup of 10-10-10 for every inch of trunk diameter (measured 4½ feet above ground level) and distribute evenly around the root zone inside and outside of the canopy’s dripline, not next to the trunk.
• For shrubs, spread 1 cup of 10-10-10 evenly around large, 5- to 6-foot-high established shrubs. Apply a half cup to small and less-established shrubs.
• For perennial flowers, rhubarb and asparagus, spread 1 cup of 10-10-10 per 100 square feet of bed, or band each plant with a fourth to a half cup. Cultivate in and water.
• For strawberry patches, follow vegetable garden guidelines.
Fertilizing Trees and Shrubs
Trees and shrubs growing in their natural habitats rarely display symptoms of nutrient deficiency. This is due not only to the natural recycling of nutrients that occurs in nature, but also to the fact that plants in the wild typically grow only where they are best adapted or have a competitive advantage.
Nursery, street tree, and landscape plantings are, for the most part, an artificial habitat. Soils may be vastly different from those of the native habitat of a given plant, and nutrient recycling systems may be altered or diminished as a result of planting schemes (planting in turf areas) or maintenance practices (collection of fallen leaves). For these reasons, periodic applications of fertilizer to the soil beneath ornamental trees and shrubs are sometimes needed to replenish essential mineral elements and to promote healthy growth.
In landscapes and field nurseries, it is important to select species that are best suited to the site. A program of cultural practices that sustains or replenishes soil organic matter and nutrients should also be established. These practices might include incorporating compost into soils at the preplant stage, applying organic mulches, and cover cropping. Proper maintenance of soil fertility and attention to plant nutritional requirements is at the heart of an effective IPM or Plant Health Care program.
A fertility program for woody plants begins with obtaining an analysis of soil pH (or level of acidity). Soil pH is measured on a scale of 0 to 14. Soils with a pH below 7 are acidic while those above 7 are alkaline. Adjusting pH levels is important not only because specific plants grow best within a certain range of pH, but also soil pH affects the availability of both major and minor nutrient elements. Furthermore, soil pH influences the level of microbial activity in soils. Microbes involved in mineralization of organic matter are most active between a pH of 6 and 7. At extremes in pH, many nutrients occur in forms unavailable for uptake by plant roots. Figure 1 at right shows the relationship between pH and availability of elements essential to plant growth.
Analysis of soil pH levels should be routinely made prior to any planting in nursery soils or at landscape sites. Typically limestone is required to adjust pH upward while sulfur is used to lower pH. It is best if these materials are incorporated into soils prior to planting, since surface applications are slow to affect pH levels. Most liming and sulfur recommendations are based on the assumption that the material is worked in to depths of 8 inches. Deeper incorporation of either limestone or sulfur will require adjustments in rates to accommodate larger volumes of soil.
What to use?
Basic plant nutrition involves the uptake of sixteen mineral elements essential to plant growth. In addition to carbon, hydrogen and oxygen, which are obtained from air and water, the elements nitrogen (N), phosphorus (P) and potassium (K) are required in greatest abundance. Research in woody plant nutrition has shown however that nitrogen is the element that yields the greatest growth response in trees and shrubs. For this reason, high nitrogen fertilizers with N-P-K ratios of 4-1-1, 3-1-1 or 3-1-2 are generally recommended for feeding established woody plants. These include fertilizers with analyses such as 8-2-2, 15-5-5, 24-8-16 and similar formulations. The analysis refers to % nitrogen, % phosphorus (as P2O5) and % potassium (as K2O) in the fertilizer.
Phosphorus, potassium and essential elements other than nitrogen are slow to be depleted from soils. Provided these nutrients are at recommended levels, a fertilizer program for established woody plants can consist of applications of nitrogen sources alone. Complete fertilizers should only be used for trees and shrubs if a soil and/or leaf tissue test demonstrates need. Typically, in New England soils there are sufficient amounts of phosphorus (P) and potassium (K).
Application of slow-release forms of nitrogen provide the most efficient use of this nutrient because root growth and nutrient absorption can occur anytime soil temperatures are above 40° F. Slow release nitrogen fertilizers are preferred over quick release water soluble fertilizers because they provide nitrogen more slowly resulting to more uniform growth. They also have lower potential impact on the environment. Quick release nitrogen fertilizers should only be used if the objective of fertilization is to restore leaf nitrogen content and green-up the plants.
On fertilizer labels, slow-release nitrogen is represented as Water Insoluble Nitrogen or WIN. Isobutylidene diurea (IBDU), ureaformaldehyde, sulfur-coated fertilizers (e.g. Sulfur Coated Urea) and resin-coated fertilizer are commonly used sources of slow-release nitrogen or WIN.
Fertilizer Math: Calculating the amount of a given fertilizer fomulation to apply per 1000 sq. ft. is based on both the results of a soil test and the % nitrogen (N) in the bag. Use the following method:
Example: Assume the fertilizer to be used is a 30-10-10 formulation with 30% nitrogen.
Area Method: In the past, determination of the correct amount of fertilizer to apply was based on the DBH (Diameter at Breast Height) of the tree or on the root area measured in square feet. Today, only the square foot method is recommended, since this reduces the risk of over-fertilization. When calculating the area of a tree or shrub bed, only measure the area where fertilizer can actually be applied. Do not include areas such as the driveway or sidewalk.
- A. Area of a square or rectangle: To measure the root area of a tree or shrub growing in a confined area that is a square or rectangle, measure the length and width of the area to be fertilized and multiply the two to get the area in square feet.
- B. Area of a circle: To measure the area of root coverage for a tree or shrub in a non-confined site, calculate the area of a circle. Measure the radius in feet from the trunk out to the drip line, or beyond for larger specimens.
Nitrogen in slow-release form may also be obtained from natural organic fertilizers. Because of a lack of industry standards for the definition of “organic” and “natural” a great deal of variability exists among these products in terms of their composition and analysis. For those adhering strictly to “organic” methods, the label of a given product should be examined for organic certification either by the state agriculture department or organizations such as NOFA (National Organic Farmers Association). The term “natural” is used here to indicate fertilizers that are not synthesized but are derived from naturally occurring materials.
Before applying natural fertilizers, the user must be aware of the nutrient analysis, i.e. the amount (by percent) of N, P and K, and the rate of release of the nutrients. Often mineral elements in natural materials, whether organic or inorganic, are released very slowly. This can benefit plants if nutrient release is steady and continuous over a long period of time. However, these materials may be of little immediate value in correcting nutrient deficiencies. Generally, slow-release materials must be applied in large amounts so that a balance exists between the rate of release and the amount of nutrients available at a given time for absorption by plant roots. Unfortunately, objective information on rates of release of mineral elements from natural materials is often lacking, in part because rate of release is a function of highly variable environmental factors.
Fertilizer labels do contain information on how fast the nitrogen will be released. The WIN (Water Insoluble Nitrogen) number will list the percent of nitrogen that is insoluble or slow-release. The WIN number is compared to the percent of total nitrogen in the fertilizer. As an example, a fertilizer with a total of 30% nitrogen and a WIN percent of 15 (50% of the total nitrogen) would be considered slow-release. That is, when the WIN is equal to or more than 50% of the total nitrogen, the nitrogen is considered to be slow-release. If WIN is less than 50% of total nitrogen, the nitrogen is considered to be fast-release. A true organic fertilizer would be almost 100% slow-release.
Compost, well-rotted manures and sewage sludge may be used to fertilize woody plants, although their nutrient composition is quite variable. Those forms of compost, manure, or sludge that are sold commercially as fertilizers will have nutrient analyses listed on the product package. When buying bulk quantities of compost materials, always request a nutrient analysis of the product. These materials can supply some nutrients and contribute significant amounts of organic matter to improve soil structure and fertility and should be a part of a soil and fertility management program. Compost guidelines for the Northeast suggest applying finished compost at a rate of no more than 4 cubic yards per 1000 square feet (3/4 inch thick layer of compost).
Rates of application
Preplant incorporation of phosphorous and potassium into soils should be based on soil test results. It is advisable to incorporate these nutrients so that they will be in the root zone when woody ornamentals are planted. This is especially important for those mineral elements that are not very mobile in soils. Phosphorus, for example, moves very slowly, as little as one inch per year from the site of application. Superphosphate (0-20-0), triple superphosphate (0-40-0), ammonium, and potassium phosphates are commonly used forms of phosphorus fertilizer. Rock phosphate is a natural source of phosphorus, but rates of application should be adjusted to accommodate the very slow rate of release of the nutrient. Particular attention must be paid to phosphorus levels in soils planted to needled evergreens since their growth response to nitrogen is greatest when phosphorus levels are high.
Preplant incorporation of potassium can provide sufficient reserves to support plant growth for five years in soils that are high in organic matter or clay content. When dissolved in soil water, potassium is a positively charged chemical (cation) and binds to particles of clay and organic matter. With high levels of clay and organic matter, potassium can be added in a single application. More frequent applications of this nutrient are necessary in sandy soils because they have less ability to bind potassium. Common fertilizer forms of potassium include potassium chloride (muriate of potash), potassium sulfate, potassium nitrate, and natural materials such as kelp meal, greensand and alfalfa meal.
Rates of application of phosphorus, potassium, and nutrients other than nitrogen should always be based upon soil test results. Any nitrogen applied as a preplant nutrient should be in a slow-release form or natural organic form.
Rates of fertilizer application are typically based upon the amount of nitrogen in the fertilizer since nitrogen is the mineral element most responsible for vegetative growth. For annual maintenance, it is recommended that a tree receive 1 to 3 pounds of actual N per 1000 sq. ft. of surface area (see Fertilizer Math above). The actual amount of a fertilizer to apply for maintenance of woody plants may be determined by the area method (see Area Method above).
Reduce the amount of fertilizer applied at any one time to trees on shallow, sandy, or poor sites, so as not to burn the plant’s roots. Using fertilizers with slow-release forms of nitrogen will also help reduce the possibilities of root injury in such situations. Rates of nitrogen application should be adjusted on sites where there is a high potential for ground water contamination from nitrate leaching. On such sites, nitrogen application rates of 1 lb N/1000 sq. ft. or less would be advisable. Several applications at these reduced rates may be made during the growing season if needed for improving plant health. Again, use of slow-release forms of nitrogen can reduce the potential for leaching.
Rates of nitrogen application should also be adjusted according to levels of soil organic matter. Applying high rates of nitrogen to soils low in organic matter will accelerate depletion of the organic matter and in the long run reduce the fertility and structural integrity of the soil. Analysis of organic matter levels may be requested when submitting soil samples for testing. Soil organic matter levels of 4% or greater are desirable. In coastal areas where organic matter content of sandy soils is often in the range of 1-2%, use fertilizers with at least 50% of the nitrogen in water-insoluble (WIN) or slow-release form. In general, at a pH between 6 and 7, it can be assumed that 1/4-1/2 pound of nitrogen per 1000 square feet is being made available per year for each one percent of organic matter in the soil. Therefore, a soil with 4% organic matter can contribute from 1-2 pounds of nitrogen per 1000 square feet per year. That is typically enough nitrogen to support healthy growth of woody plants.
Methods of application
There are several methods of applying fertilizers to trees and shrubs. The method selected depends upon soil characteristics, site factors, cost, and type of nutrients to be applied.
- Liquid soil injection: This is the method most often used by professional arborists because it is quick, easy, and also leads to rapid uptake of nutrients. It utilizes high pressure injection of liquid fertilizer into the soil. Injection points should be 2-3 feet apart depending upon pressure and about 8-12 inches deep. Slow-release forms of liquid injection fertilizers are also available.
- Drill hole: This technique requires drilling holes into the soil and distributing granular fertilizer evenly among the holes. Holes are drilled to depths of 8-12 inches and are spaced 2-3 feet apart in concentric circles around the tree, beginning at a point about 1/3 the distance from the trunk to the drip line and extending 1-3 feet beyond the drip line. While rarely used today on a commercial scale, this method is effective in opening heavy compacted soils, allowing fertilizer, water and air to reach the root zone. The holes may be left open or filled with compost, peat or other organic material. The drill hole method should be used where high fertilizer rates or fertilizers with a high salt index create a potential for injury to fine turf.
- Surface application: Granular forms of fertilizer may be spread by hand or mechanical spreader over the surface of soil around trees and shrubs. This method is quick, easy and inexpensive, and recent studies have shown this method to be as effective in supplying nutrients to plant roots as other techniques. It is particularly appropriate for applying fertilizers to mulched areas and shrub borders. A tree growing in a lawn area will utilize nutrients from surface applications of fertilizer made to the lawn and may not need additional fertilizer.
- Fertilizer spikes/stakes: With this method, solid rods of a pre-measured amount of fertilizer are placed in holes in the soil around woody plants. Wide spacing of holes and slow lateral distribution of nutrients limit the effectiveness of this technique. It is not recommended.
- Foliar fertilization: This technique entails spraying liquid fertilizers onto the foliage of plants. It is used primarily as a “quick fix” for minor nutrient element deficiencies. Foliar feeding is not effective in supplying essential nutrients in quantities necessary for satisfactory growth. The most effective time to spray foliage with micronutrient solutions is just before or during the growth period.
- Tree trunk injections: Injections of nutrients directly into a tree is used almost exclusively to correct minor element deficiencies, e.g. iron, manganese and zinc. This technique may also be used in urban settings where root or surface applications of fertilizers are not practical.
Frequency of application
Frequency of application depends on the general vigor and growth of the plant, with the exception of newly planted trees and shrubs. Woody plants growing in rich soils with continual replenishment of nutrients from decomposition of organic matter may not need regular fertilizing. However, plants that are in a nursery production cycle, as well as landscape plants that show either abnormal leaf size or color, little or no annual growth, or significant amounts of dead wood within the plant, should be fertilized annually.
Time of application
Fertilizers are best applied in late August through September. Root absorption of nutrients is very efficient in late summer and remains so until soil temperatures approach freezing. Nitrogen that is absorbed in fall will be stored and converted to forms used to support the spring flush of growth. The next best time to fertilize woody plants is early spring prior to initiation of new growth.
Trees and shrubs should not be fertilized during times of drought stress or when they are showing signs of water stress unless irrigation is available. Plants do not absorb nutrients without adequate water. Some fertilizers may also damage roots if water is lacking.
Written by: Ron Kujawski and Dennis Ryan
Fertilizing Trees & Shrubs
Nutrient Needs of Shrubs
Essential elements for plant nutrition include nitrogen, phosphorus, potassium, calcium, zinc, copper, molybdenum, magnesium, iron, sulfur, manganese and boron. They come
from the soil and from applied fertilizer. Plants obtain carbon, hydrogen and oxygen from the air or through the soil.
Certain elements–such as boron, zinc, manganese, iron, copper and molybdenum–are called micronutrients, because plants require very small amounts of them. However, they are just as essential for plant growth as the macronutrients – nitrogen, phosphorus and potassium–which are required in larger amounts.
Objectives Of Fertilizer Application
Fertilizers may help improve the appearance and condition of ornamental trees and shrubs. Increased vigor may make the plants more resistant to attack by disease organisms and insects.
Many factors influence the fertilization program of plants in the landscape. Unlike similar plants growing in the nursery, landscape plants are often growing under stress. Fertilization practices leading to satisfactory plant growth must take into account these stresses.
Fertilizer response varies with the plant and the environment. Soil fertility, aeration, drainage, exposure to sun and wind, temperature of the site, and proximity to buildings, walks and streets are but a few of the many factors that influence plant growth.
Analysis or Fertilizer Grade
The analysis or grade refers to the minimum amounts of N, P2O5 and K20 in the fertilizer. A 10-10-10 fertilizer would contain 10 percent nitrogen (N), 10 percent P2O5
equivalent and 10 percent K2O equivalent. In 50 pounds of 10-10-10, there are 5 pounds of N, 5 pounds of P2O5 equivalent and 5 pounds of K2O equivalent.
In the future, fertilizers will most likely be expressed entirely in the elemental form–N-P-K–rather than the N-P2O5-K2O used today. Then today’s conventional 10-10-10 fertilizer will be a 10-4-8 fertilizer. The percentage of P in P2O5 is 43.6, so multiplying the pounds of P2O5 by .436, gives the pounds of actual P in a fertilizer. The
percentage of K in K2O is 83, so multiplying the pounds of K2O by .83 gives the actual K in a bag of fertilizer.
If any of these elements are not present in the formulation, a zero would appear in the analysis. For example, ammonium nitrate has no phosphorus or potassium, and its analysis is 33-0-0.
To compute the number of pounds of nitrogen in a 100 pounds bag of ammonium nitrate (NH4NO3) multiply 100 x .33, which equals 33 pounds of nitrogen. Dividing 33 by the unit cost yields cost per pound of nitrogen.
Organic and Inorganic Sources
Fertilizers may be divided into two broad groups: organic and inorganic, or chemical. An organic fertilizer is derived from a living plant or animal source. Nitrogen
in an organic fertilizer is slow in becoming available for plant use because the organic nitrogen (NH2) must be reduced by micro-organisms to ammonium (NH4) or nitrate
(NO3). Generally, home gardeners tend to use organic fertilizers more than commercial producers do because of their high cost per pound of actual nutrient element. Urea however, a synthetic organic fertilizer that is 45 percent N, is available at a low cost. In moist media at a temperature above 60 degree F., it takes only about three to five days for the complete conversion of urea to ammonium.
Another organic fertilizer that may soon be used in greater quantities is sewage sludge. Plants have been shown to respond favorably when sewage sludge was applied to the soil. Further research is needed before specific recommendations will be made.
Chemical fertilizers are either mixed or manufactured and have the advantage of low cost. Consequently, most fertilizers used today are from chemical sources. High analysis, water soluble, chemical fertilizers will injury plants if not washed or brushed off the foliage.
Slow Release Fertilizers
Slow release fertilizers may be either inorganic or organic. They are characterized by a slow rate of release, long residual, low burn potential, low water solubility and they cost more than water soluble fertilizer.
The most common element in a slow release fertilizer is nitrogen. Several categories of slow release nitrogen fertilizers are commercially available, including: –Ureaformaldehyde (UF) (38-0-0). Released by microbial degradation. –Isobutylidene diurea (IBDU) (31-0-0). Released by soil moisture and particle size. –Sulfur coated urea (SCU) (36-0-0).Release rate controlled by coating thickness. –Plastic coated fertilizers (various formulations). Release dependent on temperature and coating thickness. –Natural organics–sewage sludge, process tankage and fish scrap.
Unlike most granular inorganic fertilizers, which contain water soluble nitrogen (WSN), these slow release fertilizers are primarily composed of water insoluble nitrogen (WIN), which is released slowly. The majority of the slow release fertilizers offer both rapid initial release and long term release of nitrogen.
Soluble fertilizers have gained importance over the years in landscape management and nursery production. They are widely used to prevent and correct minor nutrient
deficiencies. Soluble fertilizers are applied either on the foliage or on the soil.
Liquid fertilizers are important in production of nursery stock, particularly as additives in spray operations. Landscape and grounds personnel use liquid fertilizers extensively for deep root feeding of trees and shrubs.
The purpose of fertilizing landscape plants during the first year or two after transplanting is to increase height, width and caliper. Once the plants are
established and growing well, however, the function of fertilizing is to continue satisfactory growth and health but not necessarily to produce maximum height or caliper.
Research has shown that about 3 lbs. of actual nitrogen, the element most responsible for vegetative growth, per 1,000 square feet per year is all that is needed to maintain the health of woody plants in most landscape situations. If foliage color, annual growth or general vigor is not normal, collect foliar samples, have them analyzed and follow the recommendations that come back with the results. Otherwise, use the suggested rate as a guide.
To calculate the surface area under the branch spread of a tree, multiply the radius times itself and then multiply that by 3.14 (surface area = Radius2 x 3.14). (The radius is the distance from the trunk to the edge of the branch spread.) As an example, a 6-inch diameter trunk with a total branch spread of 36 feet would have a radius of 18 feet. The area, according to the formula would equal 18 x 18 x 3.14, or 1,017 square feet. Following the recommendation of 3 lbs. of actual nitrogen per 1,000 square feet, you would apply about 9 lbs. of 33-0-0 fertilizer (3 divided by .33 = 9 lbs.).
Woody plants respond well to fertilizers with a 3-1-2 or 3-1-1 ratio, such as 24-8-16, 18-6-12, 18-5-9, 15-5-5, 12-4-4 or similar formulations. An application of 3 lbs. of actual nitrogen per 1,000 sq. ft. applies 1 lb. of P2O5 and 2 lbs. of K2O when using a 3-1-2 ratio.
The trend in recent years has been for fertilizer formulators to use higher analyses in the fertilizer package. Often the nitrogen content is 30 percent or more
and four or five times the phosphorus level. These formulations, though promoted for turf, can be satisfactorily used around woody plants. In fact, plants with root zones beneath lawn areas that are fertilized at least three times per year do not need additional fertilizer applications. The use of fertilizer and herbicide combinations around landscape ornamentals increases the chance of herbicide injury on the ornamentals.
Timing Fertilizer Applications
In the landscape, plants are fertilized in spring and fall. Fertilizing twice a year is preferable to the common practice of fertilizing every two to three years.
The best time to fertilize is fall, generally after the first hard freeze in September or October. The next best time would be before growth begins in early spring, usually between March and early May. If fertilizer is not applied in the fall or the spring, it may be applied up to July 1. Fertilizer applied after July 1 could promote a late flush of growth that may not have time to mature before freezing temperatures occur in the fall.
Methods Of Fertilizer Application
The various methods of fertilizer application include injecting liquids into the soil, placing dry fertilizer in holes drilled in the soil, applying fertilizer to the soil surface and spraying it on the foliage. Which method you choose should depend on the site and plant condition.
With most woody plant species, surface application is as effective in provoking a positive plant response as other
methods. This method requires the least application time and is the least expensive.
Liquid fertilizer injected into the soil is rapidly taken into the plant by the roots, so injection is a good way to apply necessary nutrients. Also, the addition of water to dry soil is desirable during periods of drought. Injection sites should be 2 to 3 feet apart, depending on the injection pressure and 15 to 18 inches deep for established trees.
A major advantage to the drill hole method is the opening of heavy (clay) or compacted soils, which allows air and fertilizer to penetrate. With this technique and liquid injection you avoid the excess grass growth that surface applications cause in turf areas.
The drill holes should be placed in concentric circles in the soil around the plant, beginning 3 feet from the main stem and extending 3 feet beyond the dripline. Space holes 2 feet apart and drill them 15 to 18 inches deep. The recommended rate of fertilizer should be uniformly distributed among the holes. Fill small holes with sand following fertilization but only partially fill large holes.
Liquid fertilizer sprayed on the foliage can not provide all the necessary nutrients required by plants in the amounts needed for satisfactory growth, but it can be very
effect for correcting minor nutrient deficiencies, especially for treating iron deficiency using chelated iron.
Micronutrient spray applications are most effective when made just before or during a period of active growth, usually from spring to early summer. Plant response–
greening of chlorotic foliage and normal growth coming from buds on affected shoots–is usually observed from two to eight weeks after treatment, but response time varies,
depending on species, age of the plant and its parts, the time of year, the severity of the deficiency and the soil conditions under plants are growing. One or two
applications during the year will prevent or control deficiencies, but under some conditions it may be necessary to make several treatments annually to continue healthy growth. Using annual foliar sprays to correct a chronic nutrient deficiency is usually not a practical management practice for large trees.
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Just as your lawn requires regular fertilization for overall health, vitality and beauty, so do your landscape trees and shrubs. Why? Because trees and shrubs are plants, living organisms, which require food in order to live and thrive. This is why a comprehensive maintenance program will include tree and shrub care in addition to scheduled lawn care visits. The key nutrients are the same—nitrogen, phosphorus, and potassium—as are the issues with organic versus synthetic fertilizers (efficacy and absorption rates differ between the two). Despite these similarities, however, we don’t feed trees and shrubs quite the same way, nor do we need to feed them as often. Let’s take a closer look.
Deep Root Feeding Trees and Shrubs
When we feed a lawn, we apply fertilizers evenly across the lawn’s surface. The fertilizer materials reach the soil where they are absorbed and made available to the grass plants via their root systems (even more so if the lawn has been aerated at least once a year). By comparison, trees and shrubs tend to have larger, deeper root systems. Because not all nutrients are as mobile in the soil as others, surface fertilization may not be sufficient to reach those tree and shrub root systems. In addition, surface feeding trees and shrubs with the necessary fertilizer quantities may adversely affect the surrounding turf, whether by causing excessive growth or outright damage. A better way to feed trees and shrubs is to put the nutrients deeper into the soil. There are several methods commonly used to for this purpose, some easier than others to carry out. Spring-Green accomplishes this through a process called deep root feeding.
Using specialized professional equipment, we inject liquid fertilizers into the root zone of targeted trees and shrubs. The most effective way to do this is to make intermittent grid patterns of pressurized soil injections beginning about a foot away from the base and ending within the perimeter of the “drip line” or canopy of a given tree or shrub. The individual injection sites are about two feet away from one another and six inches deep. Smaller shrubs receive injections equally spaced around the perimeter, as close to the base as is practical. This pattern of hydraulic injections places the nutrients right in the root zone, where targeted trees and shrubs can access them.
Which Trees and Shrubs Should Be Fertilized?
Deep root fertilization is most beneficial to ornamental trees and shrubs, as opposed to mature shade trees, which are much larger and tend not to require supplemental nutrition. These smaller trees and shrubs will take up the injected nutrients and utilize them for enhanced growth and vigor above ground as well as better root development below. They will become healthier overall and more resistant to disease and insect infestation.
Spring-Green recommends deep root feeding twice a year, once in spring and again in the fall, as prescribed in our 2-Step Tree Program, which incorporates additional benefits as well. Customers may schedule an individual root feeding or opt for this comprehensive two-step program. When homeowners consider the investment they have already made in their landscape plantings, especially in light of the cost of replacing ornamental trees and shrubs, our tree and shrub care services prove to be of real value.
While reading this post, you may have developed a few questions of your own. Which of my trees and shrubs need deep root feeding? We can explain which plants should be targeted and why. Should I schedule a single service or a full program? We can discuss both options. Can I start in the fall? Yes, absolutely, whether you opt for a single service or full program. We would love to hear your questions concerning any aspect of tree and shrub care or lawn care for your home. Please do not hesitate to call on your neighborhood lawn care professional at Spring-Green. We look forward to hearing from you.