- How to Harvest and Cure Your Onion Crop
- Onion Harvest Time: Learn How And When To Harvest Onions
- Success in Harvesting Onions
- When to Harvest Onions
- How to Harvest Onions
- Drying and Storing Onion Bulbs
- Harvesting Shallots: When Is It Time To Harvest A Shallot Plant
- Growing Shallots
- When to Harvest Shallots
- How to Harvest Shallots
- All About Growing Shallots
- Harvesting and Storage
- Propagating Shallots
- Planting Onions
- Time to Plant Fall Onions for Overwintering!
- Guide to Growing Spring Onions
- How to Grow Spring Onions
- Best Time to Sow Spring Onion Seeds/Plant Seedlings
- How to Sow Spring Onions Seeds
- Spring Onion – Likes
- Spring Onion – Dislikes
- Tips for Growing Spring Onions
- How to Grow Green Onions in Water
- How to Harvest and Store Spring Onions
- How to Harvest Spring Onion Seeds
- Spring Onions – Pests and Diseases
- Spring Onions Health Benefits
- Spring Onions Recipes
- Like this article?
- What to do if your Onions and Shallots bolt
How to Harvest and Cure Your Onion Crop
Here we are, a whole season after the first onion seeds were sown, and those little specks have slowly grown into a bed of bulging, fragrant alliums.
While onions can be harvested and eaten at any stage, the most satisfying part of growing onions is being able to pluck a fresh onion from the pantry months after you’ve plucked it from the ground. Curing makes that happen.
Curing is a month-long process of drying down your onions to prep them for storage. Once properly cured, onions store for a very long time — through the fall and winter, and sometimes even spring under the right conditions. (Though I’ve never actually had an onion store through the spring, since my harvest is long gone by March. What can I say, I love onions.)
When your onions are vigorously growing through the longer days of spring and summer, their stems are lush and happy and green. You might even have a few onion blossoms topping those stems (more on those later).
When they’ve finished developing, you’ll notice the lowest leaves start to yellow and wither. Shortly after, the stems will flop over at the neck, as if all your plants had just died. The onions won’t look very appetizing either. Fear not. Wait for most of your crop to flop, then bend over the stems of any remaining upright plants. You can simply bend them above the bulb; this will signal the plants to enter dormancy.
If some of your onions have sent up flower stalks, you can just leave them be. The leaves around the stalk will still wither naturally when the onion is ready for harvest, so you don’t have to bend over the stalk. I don’t recommend cutting it off, because it could introduce bacteria into the onion during the curing process.
At this point, stop watering and leave the onions in the ground for 7 to 14 days (depending on how dry or humid your climate is) to allow them to fully mature.
On a dry, sunny day, carefully pull each onion out by the bulb, or by digging around it. Grasping the weakened stem could cause it to pull off entirely, and you want the stem intact to reduce the likelihood of rot. Lay the onions out on the ground, or in another open, sunny area, for a day or two to dry out the roots.
But wait! You’re not done yet. After a nice day of getting their tan on, move the onions into a breezy, shady spot (such as a covered porch, or under a tree) and lay them out one by one. You don’t need to clean off the onions yet. Just set them out to dry, dirt and all, until the stems turn brown and brittle. This rest period allows the onions to go deeper into dormancy so that they’re less susceptible to disease.
If you have absolutely no shade around your house, you can lay them in the sun but covered with a thin cotton sheet (never plastic or canvas, which could stifle them) to prevent sunburn. If you tend to get rain in the summer, you can cure your onions in a garage or basement, but turn them over a couple times a week to ensure even drying. The important part of curing is having plenty of air circulation around the bulbs. Because of this, it’s best to lay them out without crowding them, rather than heaping all your onions into a basket.
This last step of the curing process takes two to three weeks. You want your onions dry, dry, dry. The roots will become wiry and the papery outer skins will tighten around the bulbs.
Now you can clean ’em up by trimming off the roots and stems with shears. A couple layers of the outside skin will usually flake off with the stems, leaving you with a smooth, spotless onion.
If you had a few onions with flower stalks growing through the bulbs, use those up first. The stalks retain a lot of moisture (even after curing) and will cause the onions to decay sooner in storage. They’re perfectly fine to eat and usually keep for a month or two.
For the rest of your onions, stash them in a cool and dry, dark and airy space, inside brown paper bags, mesh bags, milk crates, wire or wooden racks, or any well-ventilated storage shelf. Sweet, juicy onions (including many short-day onions) tend to not store as well as firmer, long-day varieties, so you’ll want to use them first.
Keep in mind that even after curing, onions are still very much alive and need cool, dry conditions to stay dormant. Any change in temperature or humidity can cause them to break dormancy and sprout again. You should check your onions every few weeks for green shoots that might emerge in storage. (I once let them linger in a warm room for a couple of months, and came back to alien-like tentacles taking over my shelf. The onions were still good to eat, though.)
If you happen to have some teeny tiny onions (I usually get a few that never got around to growing, but are too small to be used like shallots), cure them and save them for next year — you’ve just grown your very own “set” of onions! Replant them in the spring, where they’ll mature into full-sized bulbs in less time… and you’ll have a new harvest even sooner!
Onion Harvest Time: Learn How And When To Harvest Onions
The use of onions for food goes back over 4,000 years. Onions are popular cool season vegetables that can be cultivated from seed, sets or transplants. Onions are an easy-to-grow and manage crop, that when properly harvested, can provide a kitchen staple through the fall and winter.
Success in Harvesting Onions
Your success in harvesting onions will depend on proper planting and care throughout the growing season. Plant onions as soon as the garden can be worked. Rich soil, consistent moisture and cool temperatures help bulb development. It’s best to create hills for onions that are to be used for green onions but do not hill those to be used for bulbs.
When to Harvest Onions
In addition to good planting, you need to know when to harvest onions for the best flavor. Harvest tops for green onions as soon as they reach 6 inches in height. The longer you wait to harvest the green tops, the stronger they become.
Any bulbs that have bolted, or formed flower stalks, should be pulled and used right away; they are not good for storage.
Bulb onion harvest time can begin with onion tops naturally fall over and brown. This is usually 100 to 120 days after planting, depending on the cultivar. Onion harvest time should be early in the morning when temperatures are not too hot.
How to Harvest Onions
Knowing how to harvest onions is also important, as you don’t want to damage the plants or onion bulbs. Carefully pull or dig onions up from the ground with the tops intact. Gently shake the soil from around the bulbs.
Drying and Storing Onion Bulbs
Once harvested, storing onion bulbs becomes necessary. Onions must first be dried before they can be stored. To dry onions, spread them out on a clean and dry surface in a well-ventilated location, such as a garage or a shed.
Onions should be cured for at least two to three weeks or until the tops necks are completely dry and the outer skin on the onion becomes slightly crisp. Cut tops off to within one inch after drying is complete.
Store dried onions in a wire basket, crate or nylon bag in a place where the temperature is between 32 to 40 F. (0-4 C.). Humidity levels should be between 65 and 70 percent for best results. If the location is too damp, rotting may occur. Most onions can keep for up to three months if dried and stored properly.
Harvesting Shallots: When Is It Time To Harvest A Shallot Plant
Many people think of shallots as a type of onion; however, they are their own species. Shallots grow in clusters and have a textured, copper-colored skin. Shallots are mild flavored and taste like a combination between onion and garlic. To get the most of your shallot crop, it’s important to know the best time for harvesting shallots in the garden. Keep reading to learn how to harvest shallots.
Shallots prefer soil that drains well and has a high composition of organic matter. The best soil pH for shallot is 6.3 to 6.8. Keeping shallot beds free of weeds is essential to good development and helps with shallot picking once the time to harvest a shallot plant arrives.
Shallots are grown from sets as well as transplants. Shallot plants benefit from a regular feeding of organic fertilizer. The root system of shallot plants is extremely shallow, and the plants need consistent water in order to thrive.
When to Harvest Shallots
Some people have a difficult time knowing when to harvest shallots. Both the plant tops and the bulbs can be eaten, so the time to harvest a shallot plant depends on the part you will be using.
The tops can be harvested within 30 days and are commonly used in soups, salads and stews.
The bulbs will take around 90 days to mature. Shallot bulb picking should begin when the greens of the plant start to wither, fall over and die. They will turn brown and become droopy while the bulbs will protrude from the soil and the outer skin becomes papery. This usually happens in mid to late summer.
How to Harvest Shallots
When it is time to harvest a shallot plant bulb, dig the bulbs, shake off the dirt, braid the tops and let them dry.
Use a digging fork to gently lift the entire clump out of the ground and gently shake off the soil. Allow the bulbs to dry out some in the garden for about a week or so, weather permitting. You can also store them in mesh bags in a cool and dry location.
All About Growing Shallots
Red and gold shallots, particularly those grown from seed, are in a state of deep dormancy in the fall, so it is usually best to wait until early spring to plant them. Seed-sown shallots grown as annuals should be started indoors under lights in late winter, so that sturdy seedlings are ready to set out four to six weeks before your last frost. Though they start out growing slowly, shallot seedlings are sturdy, fast-growing plants compared with bulb onion seedlings.
Harden off shallot seedlings for at least a week before transplanting them to prepared furrows in deeply dug garden beds. Shape 6-inch-deep furrows in a cultivated bed, and line the bottom with a standard application of a balanced organic fertilizer. Refill 3 inches of soil, and set out the seedlings 8 inches apart in all directions.
For recommended planting dates for your local climate — and to design your garden beds — try our Vegetable Garden Planner.
Keep shallots carefully weeded, and drench plants with a liquid organic fertilizer when they are 12 inches tall. Shallot plants naturally splay out as they approach maturity, as each plant will have divided into several separate plantlets. Shallots grown from cloves may produce a dozen or more small bulbs, while seed-sown varieties typically produce three perfect shallots per plant.
Harvesting and Storage
Begin harvesting shallots when the tops are actively dying back, which is usually late summer. Loosen the soil around the plants with a digging fork, pull up the plants and shake off the soil.
After harvesting shallots, cure the plants in a warm, well-ventilated place for a week, and then trim back the tops to 4 inches, and clip off the roots. Continue curing for two more weeks before trimming again and cleaning up for storage. Store cured shallots indoors, in a cool, dry place.
Many gardeners set aside small shallots for replanting, but larger bulbs will produce better crops. Seed-sown shallots are mostly hybrids that have been bred for earliness. Although hybrid seed-sown shallots often do produce flowers, their ability to grow true from seed is unknown. Under good conditions, a packet of purchased shallot seeds will remain viable for three years.
For growing advice for many more garden crops, check out our complete Crops at a Glance Guide.
Contributing editor Barbara Pleasant gardens in southwest Virginia, where she grows vegetables, herbs, fruits, flowers and a few lucky chickens. Contact Barbara by visiting her website or finding her on Google+.
Plant your sets early in the spring. Onions do best if the temperature is cool when they start to grow, and warm as they mature. Northern springs are certainly cool — and often frosty! But as the saying goes, “You can’t kill an onion — even with a hammer!”
Frost just won’t harm sets. As soon as the ground can be worked in the spring, put the sets in. In the North that’s usually in late March and early April. Gardeners in the mild winter areas of the Deep South can plant their sets in the fall and get a plentiful supply of fresh onions throughout the winter months.
Why Onions Form Bulbs
Onion sets you plant in early spring will put on a lot of green top growth before they make bulbs. You may ask, “Why don’t the bulbs start forming right away?” The answer is that before the plants can make bulbs, they first have to store energy in the top green leaves. Then they must wait for nature’s signal to put this energy into bulb making.
The plants usually get the message when the day length and the temperature are right. The onions don’t care how old they are or when they were put in the ground; when conditions are right, they simply stop making new leaves and start using the energy they’ve stored to make bulbs. The size of the onion bulb is determined by how much energy there is in the top green leaves before the light conditions signal to start diverting energy to the bulbs. The more green growth before this time, the more energy there is and the bigger the bulb will be.
Early planting is important because it gives your onions plenty of time to grow tops and to store a lot of energy for the bulbs. If you put your sets in late, they won’t have the time for a lot of top growth. As a result, there won’t be much energy available when nature whispers to the onion plant, “Make a bulb.”
The Wide-Row Method
Plant sets three to four inches away from each other in wide rows (or a little closer if you plan to harvest them when they’re small). Wide rows are useful for onions and many other vegetables because you can grow much more using less space. That’s especially important if you only have a small plot. Here’s why:
If you plant 100 onion sets three inches apart in a single row, your row will be 25 feet long. If you allow a few inches, say three, on each side of the set, the row will be six inches wide. That’s a total of 12 1/2 square feet of garden space for 100 sets. But with a wide row 15 inches across, putting the 100 sets three inches apart in all directions, your row will be just 5 feet long and 6 1/4 square feet. A wide row is easier to water, weed, fertilize and harvest, too.
In the Ground
There’s no need to make trenches or special holes for the sets. Just grasp them at the top (the pointed end) with the root end down and push them into well-prepared soil the full depth of the bulb. The soil should just barely cover the top of the onion sets. If you have some tiny sets, plant them at least an inch in the ground, so they get good contact with the soil. The sets will get a better start. After you’ve got your sets in the ground, firm the soil around them with a hoe.
Remember, if a set is planted too shallowly, it takes a long time to get started. It’s important to push the bulb all the way into the soil. It gets the onion off to a good start for producing a lot of top growth. If the onion sets are a little too deep, it won’t hurt. Later, when the bulbs are expanding, pull some of the dirt away from the sides to give the bulbs room to expand.
You may not want to plant all your sets at once. Try keeping back a few handfuls in the refrigerator. When you start harvesting some small onions to eat raw or use in salads and other dishes, replace them with sets from the refrigerator. Just remember that onion sets planted later in the spring won’t develop into large onions.
Time to Plant Fall Onions for Overwintering!
It’s a little-known fact that many seasoned gardeners aren’t aware of: you can grow onions (and shallots) in the winter. These super-hardy plants can survive incredibly cold temperatures with a little protection, and provide quality bulbs even after they bolt in the spring. As with most fall-planted crops, success is mostly a matter of timing.
Walla Wallas can be harvested green or just after bolting
Planting Fall Onions
Prepare raised beds by incorporating compost, raking to create a smooth seedbed, then direct seeding onions about 1” apart in rows 6” apart in August or September. Once the onions reach scallion-size, harvest them individually with a knife until the remaining onions are spaced 3-4” apart.
For Northern growers (those in Zone 6 and colder), mulching the plants with straw or leaves once they become established will help the plants survive the winter. In late fall, plants should be covered with low tunnels made of PVC or bent conduit and a layer of 6mil plastic sheeting. A layer of floating row cover placed over the plants in fall will improve the microclimate even more, resulting in an air temperature inside the tunnels averaging about 20 degrees warmer than outside.
Growers in warmer regions such as the South and Pacific Northwest will often need to provide some type of protection for overwintered onions, but usually low tunnels, row cover or mulch is sufficient.
Small bulbs can be harvested in late spring
The Spring Harvest
In spring you’ll find that the plants haven’t grown much over the winter, but with any luck most have survived. They will be about the size of large scallions in April, producing small bulbs by May, and generally are full grown (often very large in mild climates) by June. Many of the survivors will be sending up a scape to produce seeds, since onions are biennials—harvest the onions before or as soon as you see a scape appear, before it becomes large and starts to affect bulb quality. Just remember that these overwintered alliums won’t store very long – they should be used up quickly, just like a scallion or fresh market onion.
Bandit Leeks are a great selection for overwintering
Northern growers have fewer varieties to choose from that will successfully survive and form spring onions. They will be best served by intermediate or day neutral onions such as Valencia or Talon F1, Bandit Leeks and bunching onions like Red Baron and Evergreen Hardy White. Growers in warmer regions can grow these as well, and are more likely to have success with large sweet onions traditionally grown in winter, like Ailsa Craig and Walla Walla.
- Article on low tunnel production of bulbing onions in New Hampshire: https://colsa.unh.edu/nhaes/article/onions
- A report on the University of New Hampshire’s overwintered onion trials:
It is a little late to be talking of autumn-planted onions, particularly as autumn is fast running into winter, but I have a plan. Autumn onion sets are planted in September or October; or, if you are lazy like me, in November. These sets are immature baby onions. They don’t grow much over winter, but get a head start in spring. You can start harvesting by June, a month or two earlier than spring-sown sets. Your choice of varieties comes down to what you prefer to cook with: ‘Troy’ (yellow), ‘Shakespeare’ (white), ‘Radar’ (yellow) and ‘Electric’ (red) are all reliable.
First, sort through your sets. It’s a mistake to plant them all: you want a medium-sized (2cm, say), firm set with round shoulders. Thin, pointy ones and the bigger ones are likely to bolt in spring. Compost the duds and any that are sprouting – the packs are generous, so you’ll still have plenty to plant. Plus, you’ll plant more onions again in spring; this lot is just a bonus early harvest.
Plant the sets 18-20cm apart each way or 10cm between plants, leaving 30cm between rows (spacing determines the final size: the bigger the space, the bigger your onions will grow). Nestle them in the ground so just the tips are showing, but be gentle – the base of the bulb is easily damaged, which will kill off the set.
Onions need a ready source of food. Organic matter such as homemade compost is best; it opens up the soil, but holds on to water when it’s dry. A bucket or two for every square metre is ideal. Avoid fresh manure, which can cause bulbs to rot off. A little fertiliser added to the organic matter won’t go amiss – organic chicken manure or seaweed pellets are ideal – and double up the amount if you can’t add organic matter.
Once the onions are in, throw some fleece or netting over, because the birds love to uproot the bulbs.
So, that’s simple: tiny onions planted now to be harvested come mid-summer next year. Or so they’d have you believe. The truth is, if winter is in the least bit wet (and we’re predicted a wet one), many of the sets are liable to rot off, particularly if you have heavy soil, are late to plant or your plot is less than sheltered.
The solution is to cheat and plant sets in modules containing good-quality compost. House the trays somewhere out of the rain: an unheated greenhouse, cold frame, front porch, even under a pane of glass held up with a few bricks will work. These autumn sets are hardy enough not be bothered by the cold, but they don’t want to sit it out in the rain. Once the worst is over – say, around March – you can plant them out into the ground.
Best Onions in Fall
Growing fall onions is sometimes confusing – should you choose the long day or day-neutral ones? When should you plant? Does the color of the onion matter? How to avoid growing non-bulbing onions again this year?
Most questions come down to, “What onions can be grown this fall?”
The short answer is the sweet onions will do best in almost all locations, but there is more to the answer!
Most gardeners can successfully grow the sweet Candy onions for cooking.
Conditions for Fall Onions
There are three conditions fall-grown onions need – day-length, time to mature and temperature.
Candy is a day-neutral onion, meaning it forms a bulb with 12 – 14 hours of daylight. The map above shows approximately where the Candy onion will grow. The southern limits are short day length and the northern are too cold too early for a sweet onion in the fall.
Our grower has had excellent results in almost all regions of the US. The exceptions are south Florida, south Texas and the extreme northern states bordering Canada. Even parts of Maine have been able to grow good sweet onions in the fall!
Time to Mature
Our sweet onion needs about 90 – 100 days to mature into good sized bulbs ready for harvesting. This is just over three months, so check your freeze dates to see if you’ve got enough time.
Light frosts aren’t a concern with onions as they continue growing until the first hard freeze.
If you aren’t sure of your medium frost dates, take a few minutes to read our article on understanding your frost dates. How to Plan for Fall and Winter Gardening will get you up to speed!
You are looking for the Fall 24°F date (the orange circle) from your local historical weather data.
This brings us to temperature…
Onions are remarkably tolerant of frosts and even moderate freezing weather. They go dormant and then resume growth when favorable conditions return. Winter temperatures down to the early 20’s won’t damage onions if mulched and protected.
An old grower once told me some of the sweetest onions he ever grew were over-wintered ones.
He planted bulbs in the early fall, let them grow and mulched heavily 6 – 8 inches deep just before the first frosts. They went dormant in the winter and when spring came he removed the mulch. The onions resumed growing as spring warmed up. He had the earliest harvest of incredibly sweet, delicious onions.
He would never sell these, as they were too special! He shared them with family and close friends.
So – can you grow onions this fall?
You can have sweet onions this fall or early winter if –
- You are not in the extreme southern or northern parts of the US &
- have at least 100 days before your area expects to have a freeze of 24°F (or below).
You can have sweet onions in early winter or early spring if –
- You are not in the extreme southern or northern parts of the US &
- don’t have 100 days before you expect to have a freeze &
- don’t get below about 20°F winter low temperatures.
You can have sweet onions for early spring harvest if –
- You are not in the extreme southern or northern parts of the US &
- don’t have 100 days before you expect to have a freeze &
- do get below 20°F winter low temperatures
- by growing under heavy mulch.
Knowing these 3 factors, you will be more successful growing your onions this fall.
As the famous radio host Paul Harvey used to say, “Now you know the rest of the story!”
Guide to Growing Spring Onions
Want to grow spring onions? If you love tasty, versatile vegetables that only need minimal space and effort, then spring onions are an excellent choice! Even the tiniest plot or pot will accommodate them.
I grow all the flavoursome Alliums (Onion family). This includes garlic, leeks, onions and chives. You can swap them around in recipes and always have an ingredient to add flavour to whatever you’re cooking. If you haven’t grown them before, or are a beginner gardener, just follow the tips in this tutorial and give them a go!
Spring Onions, Shallots and Scallions!
OK – let’s get one thing straight first! If you’re confused about the names of these vegetables, it’s not surprising as they often differ depending on where you live!
Names and varieties include spring onions and shallots (Australia), eschallots, salad onions, Japanese or Welsh bunching onions (these grow in clumps rather than singly), scallions (US), green onions (China) and Egyptian or tree onions (bulbets grow in clusters on top of the stems).
Unless there’s a picture on your seed packet or catalogue, it’s often a case of wait-and-see what grows!!
So to simplify things, some varieties have a small bulb at the end of the stalk and some don’t!
You can eat these mini bulbs just like you would a normal onion. The flavour is not as intense as the much larger true onions (Allium cepa) that can be grown from seed or bulb, and can be stored.
Spring onions (Allium fistulosum) don’t have a bulb. You grow spring onions from seed. ‘Allium’ means garlic in Latin and ‘fistulosum’ means hollow stemmed.
There are also red stemmed ones that are both ornamental and taste wonderful.
Bottom line is you can use the leaves of all spring onion cultivars to flavour your cooking. So, whatever you call them (I’m going to refer to them all as ‘spring onions’ to make life easy), they are a ‘must have’ addition to your kitchen. I simply can’t live without these delicious, handsome looking edibles.
How to Grow Spring Onions
- Flavour. There are a number of cultivars – from those with a very strong flavour to mild and sweet. You can’t go wrong with your choice – they’re ALL delish!!
- Space. One of the main reasons I grow these perennial vegetables is because they provide a high yield for the minimal space they need to grow. In the subtropics, they can be planted pretty much all year round. They grow equally well in containers as in the garden. Spring onions grow in a greenhouse in winter and even in water on your kitchen bench!
Tall & skinny, they can be squeezed into all sorts of tight spaces like my Meals on Wheels planter!
- Height and Depth – Spring onions grow to about 30-50cm (12-20in) singly or in clumps, depending on which variety you grow. They have a very shallow root system so can be grown in even the smallest of pots.
In just one polystyrene box garden, I squeezed in Garlic and Onion Chives, White Onions, Spring Onions & Welsh Bunching Onions! A perfect compact edible plant choice for micro gardens.
- Grow from Seed. This is dead easy! I save mine from previous crops by waiting until the flower head matures, then chopping it off and leaving in a paper bag until fully dry (about 2 weeks). Then simply shake the seeds into the bag, scoop them out and store in self-seal bags in a cool dry place. If you are buying seed, check my list of seed suppliers. Choose safe certified organic and non-hybrid seeds, so you can save your own seeds in future years and avoid chemically grown food.
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- I sow seeds in home made seed raising mix to save money. Keep moist by misting with water and cover to maintain humidity. They germinate in about 2 weeks.
Transplant out when they are about 15cm high but you can also buy seedlings and plant out.
- I prepare the garden soil with a good handful of rock minerals, organic soil conditioner and water in well.
Best Time to Sow Spring Onion Seeds/Plant Seedlings
- Spring onions are grown for their edible stem. They are best sown during the New Moon or First Quarter phases. (See Moon Gardening to learn how to maximise your harvest by planting in harmony with nature’s rhythms).
I use this simple Moon Calendar to sow at the optimum time of the month. The seeds germinate faster, plants are stronger, healthier & grow more quickly & I achieve higher yields for no extra effort other than planting at the right time.
- Choose a variety to suit your climate. The cold-hardiest spring onion is Red Welsh, (the French call it Ciboule Commune Rouge). Benizone has violet coloured stalks and is also suited to cold areas. Beltsville Bunching will withstand hot and dry conditions more than most.
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- Succession plant spring onions every 3-4 weeks for a continual harvest during the year.
I sow spring onions and other varieties regularly for a continuous harvest all year – they only need minimal room in my garden so I tuck them into narrow spaces like in between these rainbow chard and some herbs.
- Sow 5mm (1/5in) deep, 5mm apart and about 15cm (6in) apart in rows. Up close and personal!!
- They take about 8-12 weeks to mature.
How to Sow Spring Onions Seeds
Spring Onion – Likes
- Well-drained, humus-rich soil. Add compost or worm castings from your worm farm if you have one and ensure the soil is loose and friable.
- Soil pH 6-7. Add lime if your soil is too acidic or sulphur if too alkaline. .
- Regular watering, a sunny position and being grown quickly.
- A liquid fertiliser 2-3 times while growing. To keep the leaves green, I feed mine diluted seaweed, a weak worm juice made from diluting the liquid from my worm farm or a compost ‘tea’.
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Add a thick layer of mulch to retain moisture
- Containers or in garden beds – even a small pot will be fine for these guys so long as you keep it moist.
Spring Onion – Dislikes
- Being planted near peas and beans.
- Drying out and getting stressed.
- Competition from weeds.
- Feeling hungry!
Tips for Growing Spring Onions
Spring onions are incredibly generous and good value if you know what to do with them. Even if you buy them instead of growing spring onions, you can still get more for free. Here’s how:
Cut your bought or home grown spring onions about 3cm (1in) above the root. Use the leaves in cooking and add the stem/roots to a glass with clean water to rehydrate roots. Change water daily & keep in a well lit position such as a windowsill or kitchen bench. Watch green leaves regrow. Snip as needed! Easy as that.
How to Grow Green Onions in Water
- If you are growing a bulb variety, be aware that snipping the leaves will deprive the bulb of the food it needs to grow to maturity!
When bulb varieties start to flop over toward the soil, stop watering so the bulbs can dry out for a week or so before storing.
- Using a small fork, gently loosen the soil under the plant to harvest the bulbs. Brush off the soil and trim the roots. Hang the bulbs up in bunches until the leaf tops dry out completely. Then snip the leaves off above the bulb and store in a cool, dark and dry spot. This can extend your harvest for months!
- Container grown spring onions may need more frequent watering. Use a quality potting mix that retains moisture.
Use a moisture meter to check whether you need to water.
- Keep picking the outer leaves so new ones grow in the centre.
- Propagation by Division – If growing a bulb variety, you can divide clumps most easily during winter. Slice off individual plants (including the bulb and root) by using a downward motion with a sharp knife through the clump and loosening them apart. Once separated, trim the top and roots before you transplant.
- Uses – I pop them in as a companion plant to deter pests all over my garden. As they are members of the Liliaceae family, you can expect stunning, showy flower heads too which not only brighten up the garden but provide you with free seed!
How to Harvest and Store Spring Onions
- Start snipping leaves with scissors when they are tall, green and healthy looking.
- Depending on which variety you grow, they may develop a small white or brown bulb below the green leaves.
- If it gets too cold where you live, harvest the whole plant and regrow them in a glass of water.
If you leave the flowers on the stalks to mature, the seeds will develop and you can then save for planting future crops.
- Spring onions don’t store for long in the fridge so wrap in plastic. I prefer to harvest as needed straight from the garden.
- Whilst you can pull up the entire plant, I think this is a wicked waste! If I need a whole plant, I use a sharp knife to cut the spring onion just above the roots leaving about 3cm (1 in) stem in the ground. Then I water in with seaweed and watch it regrow!
- I snip the outer leaf of alternate plants, which encourages more growth and allows each plant to recover and thicken up at the base.
- Snip flower stalks off if you want the plant to keep producing leaves. Or allow the edible flowers to grow and harvest them for use in salads, stir fries or as garnishes.
Flowering spring onions & garlic chives make an attractive edible border that can be divided over and over to grow new plants.
- Sometimes I’ve left my spring onions in the garden so long, they become as large and thick as leeks! They still have the hollow stem so are great for soups and stock.
- According to the Seed Savers’ Handbook, spring onions can be obtained by harvesting an early variety of white-bulbed onion at a very immature stage. Seeds will last 1-2 years if stored in a cool, dry place.
How to Harvest Spring Onion Seeds
Spring Onions – Pests and Diseases
- When you grow spring onions, thrips are the main pest to watch for. These small sucking insects are active in the warmer months and most common in dry weather. Check the centre of the plant periodically. Make sure your plants are moist to avoid potential problems.
They cause white, silver or grey blotches on the leaves and the tiny thrips tend to attack new leaves as they emerge.
- Sow seeds between carrots to deter carrot fly.
Spring Onions Health Benefits
- help to lower cholesterol;
- have antibacterial and antifungal qualities;
- help relieve sinus and chest ailments, asthma and bronchitis;
- contain an anticoagulant (cycloallin) which helps thin the blood and protect the heart;
- are high in sulphur so help purify the blood, clear the skin, cleanse the liver and build the immune system.
Spring Onions Recipes
- The more mature the plant, the stronger the flavour so if you want a mild onion taste, choose young slender leaves.
- Taste delicious raw when they are at their most nutritious.
- Use both the green tops and the white or brown bulb sliced in salads, salsas, omelettes, pancakes, dips, curries, chutney, stir fries and fish dishes.
Shred the green tops and use as a garnish.
- Flavour soups, casseroles, rice, noodles, vegetables, pasta, or egg, cheese and Asian dishes.
- Try these delicious recipes for inspiration or my salsa for something quick and fresh!
Sensational spring onion salsa
5.0 from 3 reviews Sensational Spring Onion Salsa This is a family favourite I make – it’s quick, easy to prepare & can be made from fresh ingredients from your garden with herbs you have in season. Author: The Micro Gardener – www.themicrogardener.com Recipe type: Appetiser/Side Dish Serves: 4 Ingredients
- 1 cup (about 3 large) tomatoes, chopped
- 4 spring onions, finely diced (on diagonal for presentation!)
- 1 small red onion, chopped
- ¼ cup chopped fresh coriander (or vary with basil, mint or parsley)
- ¼ tspn rock salt
- Coarse ground pepper
- 2 tblspns lime juice (or lemon if you prefer)
- In a medium sized bowl, stir together ingredients gently with a spoon to combine.
- Set aside in the fridge to chill for about 1 hour to allow the flavours to develop.
- Serve on crusty sourdough bread, with corn chips (GMO free!) or as a side dish to accompany curries, Mexican dishes, omelettes or your favourite meal!
- Variations: Add 1 chopped avocado, lebanese cucumber, a chilli or feta cubes.
3.1.09 3.1.09 I’d love to hear what you do with this wonderful food plant so please share your ideas, tips and recipes!
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What to do if your Onions and Shallots bolt
There’s nothing worse than going to your vegetable plot and finding that your onions and shallots have bolted. But it’s not the end of the world, you can still harvest a good crop, the vegetables may just be a little smaller.
- As soon as you see them develop flower heads you should either snip off the flower at the top of the stalk or, if the stalk is quite thick, snip the whole thing off about 1 inch above the bulb (but not the leaves). Doing this stops the plant from wasting energy on making seeds.
- Once you’ve snipped the flowers off they can be left in the ground or harvested. Those that are left in the ground won’t develop any more, but it is a good way of keeping them until you want to use them.
- If an onion has bolted it’s not necessary to wait until the foliage turns brown before you harvest them, in fact leaving them that long could cause them to start to rot or become woody.
- If some of your onions or shallots have bolted but others haven’t, always use the bolted ones first. The un-bolted bulbs have a good chance of going on to reach maturity and can be harvested later. Bolted onions will keep for a week or so in the cupboard, but it’s best to use them straight away while they’re fresh. If there are too many, they can be chopped and frozen to be used in future recipes.
Why do onions bolt?
Onions, shallots and garlic are all part of the Allium family, a plant that naturally flowers once every two years. But flowering (or bolting) isn’t such a great thing when you’re trying to grow lots of good-quality bulbs to eat.
Usually, given normal summer weather conditions, it’s easy to grow a good crop of onions, shallots or garlic without them bolting before they reach maturity. But if the spring and summer weather is exceptionally wet and chilly, it encourages onions all over the country to bolt early. All’s not lost though! Despite the fact they’ve bolted, you can still use them and they still taste great, they just don’t store as well as fully mature onions.
How to avoid bolting onions in future
The best thing you can do to avoid bolting is to plant ‘heat treated’ onion sets.
Marshalls heat treated onion sets include Rumba, New Fen Globe, Fen Early, Red Fen and Red Ray, and are available to buy between autumn and spring.
Heat Treated Onion sets can only be planted from Mid March. They arrive with us after a minimum 12 weeks of heat treatment for immediate despatch and immediate planting into pre warmed soil. Prepare your planting bed and Pre warm your soil from Mid February. Using fleece or plastic cloches, or covering the ground with fleece held down with pegs. Plant the onions as described and keep cloche or fleece on for the first few weeks. Remove once the plant tip has started growth.
There are also lots of varieties available with good resistance to bolting. These include Onion Troy, Onion Stuttgarter Stanfield, Onion Autumn Gold, Onion Sturon, Shallot Zebrune, Shallot Biztro, Shallot Yellow Moon and Shallot Picasso – many of which are available to buy from Marshalls as seeds and sets throughout autumn and spring.
Buy online onions and shallots from award winning online retailer Marshalls Seeds.