- Tips for Growing Onions with Large Bulbs
- Sprouted Onions: Can You Eat Onion Stalks?
- Can You Eat Onion Stalks?
- Other Uses for Sprouted Onions
- How Many Onions Grow from One Bulb?
- Sprouting onions: Can you use them?
- Onion Sprouts
- The process to regrow a sprouted onion is surprisingly simple.
- 15 Foods That Can Be Regrown From Scraps
- Flowering Onion
- Plant of the Week: Onion, Flowering (Alliums)
- Allium ‘Millenium’ Flowering Onion
- What to do if your Onions and Shallots bolt
- Onion Bolting
- Overwintered onions going to seed
Tips for Growing Onions with Large Bulbs
Onions don’t compete very well with other plants because they have a really shallow root system, so organic seaweed products like MegaSea will help by promoting strong root development. If you use a fish emulsion product such as MegaFish and a compost tea or soil amendment as a side dressing, such as MegaVeggie, the onions will also have all the phosphorus, nitrogen and other trace minerals necessary for really sweet onions.
If you want larger bulbs, here’s some other tips. Grow the onions until the stalks are about 9” tall, then trim the green stalks in half (so about 4-5” remains of the stalk). Then, let them grow again until they are about 12” tall, then cut in half again to 6”. Do this 3 times, which will force more energy into the roots and will promote larger bulbs.
Then after 3 times, wait until the onions mature. When you see 4” of dead brown at top of the stalks, cut water off to the onions at this point and wait a month before harvesting. This will promote a better storage capability for the onions and better sweetness. At this point, knock over the stalks with rake in one direction 90 degrees down to the ground, leaving the bulbs still in the ground. Then after a week, pull the bulbs and lay them on that side, and let them dry for at least 2 days. Then flip them over the other direction and dry the other sides. By letting them cure at least 3 days in the sun, it will make them less acidic and it will turn enzymes into sweetness so they won’t affect sensitive tummies.
Then, after this, don’t remove the dirt on the onions themselves because this will fool the onions that they are still in the ground and they won’t start to break down. This will give you 6 more weeks of storage. You can simply braid them if you like and hang them in cool spot. Onions that generally only last about a month can last up to 3 months this way!
Sprouted Onions: Can You Eat Onion Stalks?
One lovely morning, you find that your cooking onions have sprouted, and you are left with some of the most beautiful accidental green tops…
And an absolutely miserable, pitiful bulb that’s no longer worth eating attached.
It seems like such a waste.
The now sprouted onions were left a little too long, and they decided to come back to life; turning all of the energy within the bulb (the “onion” you’re used to eating) into a plant.
However, you don’t have to let all of that greenery go to waste…
It’s time to eat some stalks!
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Can You Eat Onion Stalks?
Onions are a very unique plant, in that they send up cylindrical, hollow leaves very rapidly. The thick stalk stabilizes these seemingly tender leaves, keeping them from tumbling over in the wind or rain. The bulb (the overwintering energy storehouse for this biennial plant) provides energy to the leaves allowing them to grow so unbelievably fast. If you have ever eaten green onions or scallions, then the plant will be very familiar to you.
Contrary to what you might think, the greens of a sprouting onion are indeed edible. They may not have the strong flavor of traditional scallions or green onions, but they are still an incredible alternative for baked potatoes, omelets, burritos, quesadillas, quiches, creamed chicken, and much more. You definitely want to make sure that you wash the onion leaves thoroughly, ensuring that there is nothing lingering on them from storage.
Small critters, like spiders, could be found within the root vegetables that you are storing. If you are having to remove several sprouting onions from your pantry, please take care to avoid any insects that may be living within the many bulbs.
Other Uses for Sprouted Onions
If you want a few various ways to use up these “gonners”, try one of the ideas below! Just keep in mind that some onions are GMO and non-organic; therefore, they may have chemical residues on them or waxes, and they might not produce viable seeds. If your onions are organic and non-GMO, you will have a far easier time with the following ideas.
- Growing Sprouted Onions in Water in Windows: If you would just like to see how an onion develops in its second year as a plant, your window is the perfect place to satisfy that curiosity. Soil would be far better to use, but not everyone has spare soil on hand; instead, a jar or a glass with water will do just fine! Place your onion root side down into a glass of water. Place the jar or glass in the sunniest window of the home, and ensure that it does not fall over. Change the water every two to three days to keep it clear and to eliminate any potential odors before they start.
- Planting the Sprouted Onions in the Garden to Grow Seeds: You could also plant the onions outside in your garden, allowing them to grow as big as they desire. This is also an opportunity to produce seed, as these onions will not produce more onions; just seeds. You could get hundreds, if not thousands, of viable seeds for sowing in the fall!
- Planting Sprouting Onion Bulbs for Green Onions: If you don’t plan to keep the seeds from the sprouted onions, you could instead plant them for a continuous harvest of green onions! Just cut the flower stalk when it begins to form, and continue to harvest your green onions for culinary use.
How Many Onions Grow from One Bulb?
One onion, one bulb.
One bulb, one onion.
The bulb is the onion, and the onion is the bulb. Great! A lot of people are quite confused by this concept, especially when it comes to wondering how you produce MORE onions for consumption. Now that you’re in tune with onion bulb itself, let’s go over the life cycle one more time:
- An onion seed is planted, and a young onion seedling emerges.
- A few months after sprouting, the plant begins to thicken, lengthen, and mature. A bulb begins to form.
- As the longest days of the year come and go, this tiny little bulb begins to store energy, producing an onion bulb.
- As the bulb nears maturity, the tops die off.
- At this point in a garden, the bulbs are then harvested and cured/dried for longevity; giving you the onion you know and love.
- *IF* the onion bulb is left in the ground *OR* replanted, it will pursue it’s final year of life: when spring comes, the onion grows.
- This time, the bulb assists the onion plant in growing rapidly, far faster than any seedling would.
- Once the plant is, once again, at mature size, it will send up a flower head.
- The flower is then pollinated, and the seeds form. The plant dies, and the cycle repeats itself with the newly dropped seeds.
Sprouting onions: Can you use them?
QUESTION: Many cookbooks suggest not to use the green sprout from garlic if there is one. Does the same apply for a green sprout from an onion? — Prudence Cole, Grosse Pointe
ANSWER: This happens often. We’ve all come across onions that have hung around a bit too long. And that green sprout is one indication that the onion is old. (Note: When you buy loose onions, there’s no best-by or use-by date.)
As for the green sprout itself, you can eat it, though it may not taste all that great.
“It is safe to eat, but it does emanate from a decaying bulb and doesn’t have that green color that chlorophyll makes,” says Jim Huston of Horizon Produce in Birmingham who was a pioneer of the first sweet onions grown in South America. Huston also says you can plant that sprouted onion bulb.
Some sources say you can use that green sprout as you would a green onion.
If you find a green spot in the onion when you cut it open, remove and discard it.
During the winter, I love a good French onion soup with a cheesy topping. The accompanying recipe is a favorite.
Here are some onion tips from the Free Press Test Kitchen:
Buying: Choose onions that are heavy for their size and show no signs of decay. The papery skin on an onion should be dry with no black powdery-like mold. The onion should be hard and have no soft spots or scent. The papery skin should be tightly closed at the area opposite the root end.
Storing: In perfect conditions, onions can last more than several weeks. Store onions in a cool, dry place that has good ventilation. Don’t store onions near potatoes. It’s best not to store them in the refrigerator where their odor can permeate other foods. Once an onion is cut, wrap it well in plastic wrap or place in a sealed container. A cut onion will last about a week in the refrigerator, according to the National Onion Association. You also can chop, dice or slice onions and freeze them in freezer-quality bags. There is no need to thaw them to use in cooked dishes.
Cooking: When sautéing onions (and garlic, too) do so on low to medium heat. If the heat is too high, the onions will burn and turn bitter, adding bitterness to whatever you are cooking.
Note: Since garlic is a cousin of the onion, let’s tackle its green sprout. I am in the camp with many sources, chefs and cooks that say the green sprout is bitter and should be removed. This is especially true if you are using the garlic raw. If the garlic is to be heated or cooked, as in sautéing, it’s not totally necessary to remove that green germ. Typically, whatever you cook the garlic with, say sautéing it in olive oil and adding other ingredients, should mask any bitterness from the garlic sprout.
Have a question? Contact Susan Selasky noon-3 p.m. Thursdays at 313-222-6432 or e-mail [email protected] Follow her @SusanMariecooks on Twitter.
Caramelized Onion Soup
Serves: 6 (main dish servings) / Preparation time: 20 minutes / Total time: 2 hours (not all active time)
2 tablespoons canola oil
4 large onions, peeled, halved, sliced 1/4-inch thick
Salt and freshly ground black pepper
1 tablespoon butter
1 tablespoon all-purpose flour
1/2 cup dry white wine
8 cups low sodium, fat-free beef or chicken broth
1/2 baguette, cut into as many 3/4-inch slices as needed to cover 6 soup crocks
11/4 cups shredded Swiss or Gruyère cheese
In a large soup pot, heat the oil over medium heat. Add the onions and season lightly with salt and pepper. Cook the onions gently, stirring frequently, until they’re very soft and have begun to turn a dark golden color, about 35 to 45 minutes. (The onions will cook down considerably.)
Stir in the butter and allow it to melt. Stir in the flour and cook for 3 to 4 minutes, stirring frequently. Pour in the wine and increase the heat to medium high, stirring and scraping to loosen any caramelized juices, until the liquid is mostly reduced, about 5 minutes. Add the broth and bring to a simmer. Season to taste with salt and pepper and simmer for 20 to 30 minutes.
Taste and adjust seasonings if needed. You can make the soup up to the this point, cool and then refrigerate for 2 days.
To serve: Preheat the oven to 350 degrees. Put the baguette slices on a rack and bake until lightly toasted; set aside. Increase the oven temperature to 425 degrees.
Bring the soup back to a simmer. Set 6 ovenproof soup crocks or ramekins on a heavy baking sheet and ladle the soup into the crocks. Float two toasted baguette slices on top and sprinkle with about 2 tablespoons of the cheese (or more if you like).
Bake until the cheese is melted and lightly browned, about 8 minutes. Remove from oven and serve immediately.
Adapted from www.finecooking.com. Tested by Susan Selasky for the Free Press Test Kitchen.
Yields approximately 1 Cup (1/2 lb.) of Sprouts.
Seed Prep Measure out 4 Tablespoons of seed* Rinse your seeds to remove dust or debris. There tends to be some plant matter in with the seeds of Alliums. This plant matter is nothing but small pieces of the plants which the seeds grew on. This plant matter has so far eluded the massive seed cleaning methods used on sprouting seed. They will not elude you! These dry plant bits usually float, so the perfect time to get rid of them is before you Soak – during seed Prep and/or after the seeds have soaked for 8 – 12 hours – pour off the floating stuff. You can help by stirring the seeds up – thus helping any non-floating bits to surface from below. Easy isn’t it?
Soak Transfer your seeds into your Sprouter (if necessary), or a bowl. Add 2-3 times as much cool (60-70 degree) water. Mix seeds up to assure even water contact for all. Alliums tend to float. Try to sink those that do by knocking them down with your fingers. Most of those floating seeds will sink during the hours they are soaking, but it is a good habit to pay attention to your seed’s needs, and this is the perfect place to start! Allow seeds to Soak for 8-12 hours.
Sprouting Empty the seeds into your Sprouter (if necessary). Drain off the soak water. You can use it – it has nutrients in it.
Rinse thoroughly with cool (60-70°) water. Drain thoroughly.
Set your Sprouter anywhere out of direct sunlight and at room temperature (70° is optimal) between Rinses. This is where your sprouts do their growing. We use a counter top – in the corner of our kitchen, but where the sprouter won’t get knocked over by cats, dogs, kids or us. We don’t mind the indirect sunlight or the 150 watts of incandescent light, because light just does not matter much. A plant can only perform photosynthesis when it has leaves. Until a plant has leaves, light has little if any effect. Sprouts also happen to like air-circulation, so don’t hide your sprouts. This is most true with Alliums because they can begin photosynthesis as soon as they sprout. Unlike other seeds, Alliums sprout their plant first, not their Root.
8-12 Hours Later: Rinse and Drain again Alliums take A LONG TIME to germinate! Continue Rinsing and Draining Thoroughly, 2-3 times a day. Once your seeds germinate – Drain more gently. After many years of growing these I’ve determined that because the seeds are relatively sharp, they will sever the tender roots from neighboring seeds if spun too hard. Though Draining should still be thorough, but do use more gentle motions to get the water out of your sprouter. You will be Rinsing and Draining this crop for 10-15 days. You should see some sprouting action in between 4 and 7 days. Don’t give up – EVER – they will sprout!
Note: Alliums are unique in that the sprout they produce is actually the plant – as opposed to the Root – which is what almost all other seeds produce during the sprouting process. These plants look like – and are – tiny little Greens – like micro-scallions! As soon as these micro-scallions emerge from the seed they are able to take up light – because they are the leaf! You don’t have to do anything drastic but you can move on to……
Greening Once you see sprouting, Relocate your sprouts – if necessary. If you’ve been keeping them away from light for some reason, move them. Avoid direct sun – it can cook your sprouts. Indirect sunlight is best but virtually any light will do. Experiment – you will be amazed at how little light sprouts require to green up.
Continue to Rinse and Drain every 8-12 hours. As long as you grow: You have to keep your sprouts happy.
Finishing Your sprouts will be done between day 10 and 15. The majority of sprouts will have long thin micro-scallions, which will be green if you exposed them to light. You can eat them at any length but if you let them get to an inch or more the seed itself will be more tender.
The seed of an Alliums is pretty intense. Though they can not be dehulled like some crops – if you grow for a long enough time, some of the seeds will fall away from the sprout.
Harvest These sprouts can not be De-Hulled like some crops, but you can use our Dehuller, or any salad spinner after your final Rinse. Doing so will allow the seeds that have fallen off the sprouts, to fall to the bottom – and hopefully, through the device’s mesh, as well as allowing you to go directly to refrigeration with your crop – after spinning it dry. If you are not using such a device… Your sprouts are done 8-12 hours after your final Rinse. After the final Rinse we need to Drain Very Thoroughly (though gently) and let our sprouts dry a bit. If we minimize the surface moisture of our sprouts they store much better in refrigeration, so we let them sit for 8-12 hours….
Refrigerate Transfer the sprout crop to a plastic bag or the sealed container of your choice. We have Produce Storage Bags that can extend shelf life substantially. When it comes to knowing if your sprouts are still fresh after they’ve been in the fridge for a while, we often rely on smell. When checking Allium sprouts, remember what they smell like when you harvested them, so you don’t mistake their smell for them having gone bad. The smell they share is nothing like the smell of decomposition, but I wanted to make sure you knew about their massive aroma.
*Seed to Use
* If using Sproutpeople’s Single Harvest Pack – use the whole bag (for a one-quart Sprouter). It will produce a crop of approximately 8 ounces.
These seeds yield approximately 4:1 – which means the sprouts will weigh 4 times as much as the seed you start with, but, they will increase even more in volume – so don’t start with more than 4 Tablespoons per quart/litre of sprouter capacity, at least until you are familiar with your crop.
Wondering what to do with that sprouted onion in your produce basket? What if I could show you how to use it to grow a brand new onion in your garden?
Do you ever find an onion that has been at the bottom of the pile and discover it has started sprouting? Whenever I would find a sprouted onions, I used to get so upset that I had wasted food.
Then one day I started wondering whether I could use that sprouted onion to grow a new onion.
I found a whole lot of information saying that it wasn’t possible. Then I stumbled across this post, and it gave me new hope. I decided to give it a try next year, and I was so excited that it worked!
I love gardening tips and tricks, which is why I collect gardening books like Square Foot Gardening and Backyard Gardening on an Acre (More or Less).
Of course, you can get some onion seeds and grow onions from seed, but it’s so much fun to re-grow sprouted onions.
The process to regrow a sprouted onion is surprisingly simple.
1. Cut carefully into the onion lengthwise to expose the center sprout.
2. Remove the outer layers of the onion, until you just have the center sprout remaining. As long as the outer layers of the onion are still firm, you can eat them. If they’re soft, discard them.
If there are multiple sprouts like this one, separate them.
3. Place the onion stem into a cup or bowl of water, and leave it there until roots start to sprout. These are the beginnings of roots. I like to leave them in the water until they’re a bit longer.
Also, notice that this one doesn’t have really long green sprouts. You can also cut the center out of onions that haven’t started fully sprouting and regrow them!
4. Once you have roots developed, transplant the onion into the ground or a container full of good potting soil. I didn’t separate these ones, and they didn’t grow right. Take my lesson and separate all of the sprouts before planting.
5. Let them grow through the season. You can usually tell that the onion is done growing when you see the bulb emerge from the soil, or the green sprout starts to wilt and brown.
If you leave them too long, they’ll soften and rot. If you pull them at the right time, you’ll have beautiful onions that you grew practically for free!
In case you didn’t know, you can also re-grow green onions after using them!
Be sure to check out Square Foot Gardening to learn how to grow more in less space and Backyard Gardening on an Acre (More or Less) to learn how to grow your own food in your backyard.
15 Foods That Can Be Regrown From Scraps
Apr 22 Posted by Crystal // 87 Comments ”
I love gardening.
Well, not actually the work behind the gardening so much – it’s the harvesting that I really look forward to. There is nothing like fresh veggies from your own personal garden! I actually just planted a bunch of things in my vegetable garden, and may have gone a little plant happy at the feed & seed store. Oops.
Obviously, we all know about the normal ways to grow plants – from seeds. But, did you know that there are a ton of plants that you can grow from scraps? Plants, that will in turn, produce more food. I did some research on this through various sources, and compiled this list.
Let’s count them out – from 1 to 15…
1, 2, 3, & 4. Spring Onions, Leeks, Scallions, & Fennel
These are the ones I regrow the very most, I always have a mason jar of green onions regrowing above my kitchen sink. The technique is quite simple. Once you are done with them (any of the above four), simply place the root end in a jar of water & it will begin to regrow within just a few days. Just make sure to replace the water with fresh as need be.
You can regrow lemongrass the same way you regrow the green onions. Simply place the root ends in a glass of water, refreshing the water as needed. You will want to wait to harvest your lemongrass until it is about 12 inches tall.
Plant a small chunk off of your piece of ginger in potting soil with the newest buds facing up. Ginger enjoys non-direct sunlight in a warm moist environment. Before long, it will begin to regrow shoots and roots. Once the plant is established and you’re ready to harvest, pull up the whole plant, including the roots. Remove a piece of the ginger, and re-plant it to repeat the growing process.
Pick a potato that has a lot of good formed eyes, and cut it into 2-3 inch pieces, taking care to be sure that each piece has at least 1-2 eyes on it. Leave the cut pieces to sit at room temperature for a day or two, which allows the cut areas to dry. Potato plants thrive on a high-nutrient environment, so it is best to flip compost into your soil before you plant. Plant your potato pieces about 8 inches deep with the eye facing up. Cover it with 4 inches of soil, leaving the other 4 inches empty. As your plant begins to grow and more roots appear, add more soil.
8. Sweet Potatoes
You will need sweet potatoes with good formed eyes, just as you would want with a regular potato. You can bury the entire potato or use pieces under a thin layer of topsoil in a moist place with plenty of sun. When the shoots begin to reach a height of four inches you will need to replant the sweet potatoes, allowing them about 12 inches between each another. It takes about 4-6 months to grow sweet potatoes this way.
9, 10, 11, & 12. Romaine Lettuce, Celery, Bok Choy, & Cabbage
These all are regrown by placing the roots in a dish of water. Cut the leaves or stalks off to about an inch above the roots. Place the root end in a dish of water. Make sure that the roots are inside of the water, but do not submerge the rest of the plant. Place in a sunny window & spray with water 1-2 times a week to keep the top of the plant moist.
Onions are one of the easiest vegetables to regrow from scraps. Just cut off the root end of your onion, leaving a 1’2 inch of onion on the roots. Place it in a sunny location in your garden and cover the top with soil. Make sure to keep the soil moist by watering when needed. As you use your home-grown regenerated onions, keep replanting the root ends you cut off, and you’ll never have to purchase onions at the store again.
You can re-grow a plant from a single clove. Simply plant it with the root-end down. Sit the plant in a sunny window. Once established, cut back the shoots and the plant will put all it’s forces into producing a nice garlic bulb – full of flavor & capable of repelling sparkly vampires. You can repeat this process with a clove from the new bulb you have just grown.
To re-grow pineapples, you will need to remove the green leafy part at the top and take care that no fruit remains attached. Either hold the crown firmly by the leaves and twist the stalk out, or you can cut the top off the pineapple and remove the remaining fruit flesh with a knife. If you do not remove all the fruit parts, it will rot after planting and will likely kill your plant. Carefully slice small, horizontal sections from the bottom of the crown until you see root buds (the small circles on the flat base of the stalk). Remove the bottom few layers of leaves leaving about an inch worth of them at the bottom of the stalk. Plant your pineapple crown in a warm and well drained environment. Water your plant regularly at first. Once the plant is established, you can cut down to about once a week. You will see growth in the first few months but it will take about 2-3 years before you are able to harvest.
You can watch me give a live demo on this blog post on Fox8 News by clicking here.
posted by Crystal on April 22, 2013 — 87 Comments “
I love onions. I think they’re delicious in almost any dish. I use onions routinely constantly in my kitchen, so I always have plenty on hand. Sometimes I have too many, and they sprout in my pantry before I can use them. But that’s not such a bad thing, because I plant them and grow more onions.
Before I started my raised bed garden, sprouting onions and other kitchen scraps got tossed in the trash without a second thought. Now our kitchen waste goes into the garden instead of the landfill.
So here’s to yet another plant you can have fun growing in your garden space! But before you get started, here are answers to a few of the questions I had in the beginning…..
Do I need to separate the onion?
This spring I tried planting cut bulbs and whole bulbs. Honestly, I can’t tell one from the other growing in the garden. From the ground up, all the green onions look the same. From now on, I won’t bother to separate the bulbs because they seem to grow fine either way. But you do need to make sure that roots are visible at the base of the bulb. See the tiny white roots growing from the bottom of the bulb?
Can I grow them in a container?
You can plant sprouting onions directly in the ground, in a deep container or in a raised bed garden. As you know, I grow mine in my raised beds. Plant just deep enough so the green shoots (sprouts) are not covered. So root base down, sprouts up.
Will I get a bunch of onion bulbs?
No, but you will get a bunch of green onions! Sprouted onions will produce green onions, not more bulb onions. This is because bulb onions are biennial, which means they grow and produce bulbs in one growing season. So when you replant bulbs that have started to sprout, their main purpose for growing is to flower and produce seed. They won’t produce another edible bulb. So if you love green onions, it’s still a win!
Why are my green onions flowering?
As I mentioned earlier, sprouting onions have one main goal and that’s to flower and produce tons of seeds. So as the shoots get larger and taller, you’ll eventually see a flower head forming like the one in the picture above. You can still harvest the green onions to eat, or you can allow them to continue growing into beautiful and unique globe shaped flowers. Not only are onion flowers beautiful, they will attract tons of bees that will pollinate your garden.
When can I harvest my green onions?
I begin to harvest onion greens once they are anywhere from a few inches to a foot tall. I pretty much cut them when I need to use them. I typically add green onion shoots to omelettes, stir-fries, soups and salads.
Simply enough, right? So give it a try. Get your hands dirty. Have fun. But most of all, find ways to grow along with the plants you grow in your garden.
Although they’re onions, these ornamental plants have no unpleasant scent unless cut. Some are actually sweetly perfumed. Alliums are useful in the garden because they bridge the gap between spring-flowering and summer-flowering bulbs. Most bloom for several weeks in June and July.
Description of flowering onion: Alliums bear spheres or loose clusters of star-shaped flowers in shades of pink, white, blue, purple, or yellow. There are both tall-growing species (to 4 feet or higher) and miniature ones. Their attractive leaves, often a lovely blue-green, appear in early spring but fade away in early summer, often just as the plant is flowering. Ease of care: Easy.
Growing flowering onion: Plant small bulbs 3 to 4 inches deep, large ones 6 to 8 inches deep, in a sunny, well-drained area. Winter mulching is advisable in colder climates.
Propagating flowering onion: By division or seed.
Uses for flowering onion: Low-growing alliums are ideal plants for borders and rock gardens. Tall-growing alliums make wonderful cut flowers; soak their stems in cold water for 10 minutes to remove any scent of onion. They are also attractive in beds and borders of all sorts.
Flowering onion related species: Allium giganteum produces huge 6-inch globes of purple flowers on top of 3- to 6-foot stems and may require staking. Drumstick allium (A. sphaerocephalum) bears 2-foot stems with smaller clusters of reddish purple flowers. Blue garlic (A. caeruleum) is similar but with blue flowers. Yellow allium (A. moly) produces yellow flowers in loose clusters on 10-inch stems. A. neapolitanum is similar but with beautifully perfumed white flowers; it is hardy only to USDA zone 6.
Scientific name of flowering onion: Allium species
- Bulbs: Want to learn the basics of flower and plant bulbs? Try this article.
- Gardening: Want gardening basics – start here with our guide to gardening.
- Bulb Gardens: We answer all your questions about bulb gardens.
- Garden Types: Learn about the various types of gardens, and which is right for you.
Plant of the Week: Onion, Flowering (Alliums)
Allium ‘Millenium’ Flowering Onion
Millenium flowering onion blooms in late July and August and adds a dependable clump of color to the late season flower bed. (Image courtesy Gerald Klingaman)
While I try to live a life centered on moderation, I admire people who are passionate and obsessed about things that interest them. One such individual is Mark McDonough, a gardener who has a passion for ornamental onion. One of his onions, Allium ‘Millenium’, is now in bloom in the rock garden and shows the results a long and unwavering commitment can have on the garden world.
Alliums consist of about 850 species of Northern Hemisphere plants currently classified as belonging to the amaryllis family. The center of distribution is the Mediterranean region and the Middle East but they are widely distributed with more than 120 species found in North America.
Millenium ornamental onion is one of the rhizomatous alliums in the section Rhizirideum, a group of plants that still produce bulbs, but they are smaller and borne on a horizontally spreading rhizome. Bulbous onions, such as the sweet onions we eat and the giant ornamental onion (Allium giganteum) have large individual bulbs and the foliage dies down after flowering. The rhizomatous onions, with chives (Allium schoenoprasum)being a good example, are clump forming with flowering usually later in the year and with foliage that persists through the summer.
In three or four years, expect Millenium to form a clump about a foot across with flowering stems about a foot tall. The leaves are flat, a half-inch wide and 8 inches long, bright green and persistent throughout the summer and slightly garlic scented when crushed.
The pinkish-lavender flowers are individually about three-eighths of an inch across with six tepals (petals) but are borne in a dense umbel that forms a head about three inches across.
The stems are stout with the umbel held upright on the end of the scape. Because this hybrid, possibly between Allium nutans (Siberian chive) and Allium senescens (German chives), set no viable seeds, the clump usually remains in bloom for a month or more during midsummer.
Millenium is the misspelling originally used by McDonough for this 2000 introduction. As a self-taught expert on all aspects of alliums, McDonough sticks with the original spelling because the inscrutable rules of taxonomy place great emphasis on consistency even though modern word processing programs insist on correcting the flub.
Mark McDonough, an architect by training, gardens in Pepperell, Massachusetts. He noticed his first flowering onion as a teenager and has been collecting and growing them for over 35 years. He does not have a nursery but releases plants, so far unencumbered by patents, trademarks and other such covenants that seek to control propagation, to plantsmen who will get his hybrids into the trade.
Millenium ornamental onion is an easy to grow plant that can be used in the rock garden, mixed in the perennial border or added to the foreground in foundation plantings. Plants are deer proof and attract lots of bees and butterflies to the summertime garden. It should have at least 6 hours of sun a day and reasonably well-drained soil but does not seem finicky about soils. Plants are hardy from zones 5 through 8. Division can be made anytime from late winter until early summer.
By: Gerald Klingaman, retired
Retired Extension Horticulturist – Ornamentals
Extension News – August 4, 2014
The University of Arkansas Division of Agriculture does not maintain lists of retail outlets where these plants can be purchased. Please check your local nursery or other retail outlets to ask about the availability of these plants for your growing area.
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.
Onion bolting occurs when onions have decided to send up a flower stalk and go to seed, which happens for the following reasons:
- They’re mature, have already made their bulb and want to make seeds before they go dormant.
- They got a couple of weeks of below 50° weather
- They had a cold wet spring and then it got suddenly hot
- They got too dry, or they stayed too wet
In all these cases, the bolting onion thinks it’s going to die before it can bulb, so it puts all its energy into trying to make seeds right away instead.
Some folks will tell you to just bend over the flower stalk when it forms, or to just prune them off. I’ve even read that you should bend over all the green tops.
But once onion bolting starts, onions cannot be convinced otherwise and it’s best to dig them up for immediate eating as “green onions”. Bolting onions will only very rarely recover and form a large bulb, and even if they do, the bulb storage quality will be low. This is because the plant took the energy from the bulb and used it to send up the flower stalk.
To keep onions from bolting in the first place, protect them over an extended cold, wet spell by covering them. The best way is with a little hoop tunnel, which keeps them out of the weather entirely and can easily add 10 degrees of temperature.
Alternatively you could cover them with Reemay (or other brand) floating row cover. This is let involved, but doesn’t work as well.
And if the weather turns suddenly hot, make sure to keep your onions evenly watered. The soils needs to stay loose and friable. If it starts to get that baked-hard quality, onions will bolt because they can’t expand.
To learn more about growing onions check out these related articles:
- How to Grow Onions
Onions need soil that is loose and evenly moist so that they can easily push it aside when they start to form bulbs. This is the main how-to article that describes the best soil conditions, how day length affects bulb growth, fertilizing correctly, and how proper watering can prevent disease.
- Types of Onions
To grow large bulb onions it’s very important to choose types of onions that match how far north or south you live, because onions need to experience a certain day length before they switch from growing green tops to forming bulbs. Find out which types (and varieties) will work for you!
- Planting Onions
All about planting onions: how deep and how far apart to plant, the difference between growing from seed, onion sets or onion transplants, and when to plant onions for maximum bulb growth.
- Growing Onions from Seed
There are some advantages to starting your own onions from seed, but you’ll need to start them indoors in order to get a jump on the season and give your onions enough time to develop bulbs. Find out how and when to plant, and when to transplant outside.
- Onion Diseases
Most onion diseases are a lot easier to prevent than to cure. Learn 5 ways to prevent onion diseases, and find out what to do if your plants do become sick.
- Harvesting Onions
Make sure to wait for harvesting onions until the tops start turning brown. Learn the proper way to harvest and cure onions for the most successful winter storage.
- Storing Onions
There are several cool and clever ways to store onions, but the most important things are to provide excellent air circulation and to keep them dry. Read about tips and tricks for storing onions.
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Overwintered onions going to seed
Hmm interesting. We’ve had what I would have called a more ‘normal’ early spring here but then later spring has been unsettled. I was thinking of the phrase “April showers bring May flowers”, which hasn’t happened until this year. For the last 2 or 3 years at least we’d had dry Aprils and wet Mays so it had been confusing for my plants. This year we had a wet April, though I’d say that May didn’t fulfil it’s promise of brightening up. Not so much wet as varied with hot weeks then cooler than average weeks. Perhaps this has confused the plants.
There was a dry week in early May as I remember having to go out with the hosepipe to water the whole garden (normally I wouldn’t need to in May).
Certainly overall my plants are different to previous years. My flower seedlings germinated quickly and very well, got to 2 inches and then just stopped. They didn’t die and didn’t grow. They’ve been like that for 3-4 weeks. My dad lives 100 miles north of me and said exactly the same happened with his – different seeds, different soil, etc. That includes seeds that are either in the house, greenhouse or under cloche.
I’ve snapped the seed heads off the onions. If this works then I’d definitely overwinter them again. I put half in to overwinter and the rest in early spring. Half of the spring ones disappeared, whereas all the winter ones are still there and growing beautifully. Just as long as they’re edible at the end of it all;)
I did notice that it was mainly the red onions that tried to seed rather than the white.