Grow onions from onion

CFL’s can produce light a lot closer to the blue spectrum than any incandescent light can and for less money and they hands down last longer. Any photographer will tell you that incandescents tend way more to red, ever take a photo indoors with a film camera (using daylight film) and get that nasty yellow cast to your photos, that’s because incandescent light is nowhere near daylight temperature. Today we don’t have that problem because digital cameras automatically white balance for the light in the room. I agree with you that LED bulbs are da bomb but so far I have yet to see a LED bulb that is on the cheap side that can produce light close to daylight spectrum, I know they exist but they are generally a sort of panel setup not something you plug into your lamp and very very expensive. So for now, if you need near daylight color light and can’t afford a few grand for a professional setup cfl is it.

A friend had an indoor garden using cfl, he had blue for one cycle and red for the other (grow vs. bloom) the plants did well without spending three grand for something like a mercury vapor tech bulb which needed an expensive ballast and sucked a lot of power and made a LOT of heat as well. I think by noise he means the ballast may make “noise” on the circuit which only some very sensitive equipment would be bothered by. In the old days computer techs would tell people not to plug into a circuit with any device that pulled a lot of amperage when it first started up, that included AC units, compressors (as in your refrigerator or a shop air compressor) or vacuum cleaners because that startup usually caused a sort of brown out and then a surge which could damage circuitry and something that created noise in the circuit might affect the shape of the sign wave in the AC current also possibly causing a problem. Tech has grown past a lot of those issues.

Many years ago I recall watching a PBS science show (possibly a NOVA) that investigated how fluorescent bulbs in the workplace could be causing fatigue to people who work under them all day long. While you cannot consciously see a fluorescent bulb flash (incandescent is a heated element while fluorescent tech is a gas that gives out light when it is excited by the small amount of power supplied by the ballast thus the flashing) subconsciously your brain can see the flashing and that could lead to fatigue. The solution for that issue was a ballast that created a faster update but the bulbs were pretty expensive, I do not know the current state of fluorescent tech as to if the new stuff out right now updates faster than the old ones did.

There is a growing belief that some folks are more sensitive to magnetic fields than others and it could cause health issues. Remember those stories about farmers with AC transmission lines over their farms who claimed their cows stopped giving milk? There have also been some reports that people who live near maglev train tracks complain of constant headaches and depression, our brains are electrical why would it be such a stretch that we could be affected by magnetic fields? In Europe there is growing support for an illness called EHS or electromagnetic hypersensitivity syndrome. People with this issue need to live away from all magnetic fields some are so sensitive that even the alternator in the car causes them discomfort, you may say baloney…well no one believed that fibromyalgia or chronic fatigue syndrome were real either for quite some time. Ever have an MRI and wonder why you felt so exhausted afterwards? MRI uses one heckuva strong magnetic field to literally change the magnetic field in your body to create the images. Don’t laugh off the idea that some folks could be adversely affected by magnetic fields there may be something to it but I really doubt a couple of cfl bulbs could be an issue but who knows. Remember when cell phones came out, some folks said having them so close to your brain might cause brain tumors and the use of a headset was strongly encouraged. Well somebody also said that when we turned on that new gigantic collider in Europe that we’d open up pinhole singularities all over the world and end our existence too. The point is that we don’t know everything.

While it’s been shown that plants have at least a simple nervous system (nothing like we have) I’m sort of doubting any negative effects from a cfl bulb. Plants like light and proper soil salinity and water salinity, if they don’t get it they don’t grow as well and that’s that.

I don’t know about you, but the tail end of a long and cold winter really makes me anxious.

Here in southern Vermont, the snow and ice continue to fall even after the spring equinox makes her remarkable debut, seemingly teasing those of us who are itching to get their hands into the soil and begin the process of waking up the earth.

Planting onions and other alliums at the very end of the winter is one of the best cures for spring fever.

When farmers and backyard gardeners are ready to begin, but there is still frost on the ground, many will check their seed stock, order what they will need for the coming season, and prepare their available indoor growing space.

Geography Determines Your Growing Season

In some parts of the country, it is possible to have a consecutive growing season, without the threat of freezing temperatures or frost. In those places, there is no need to begin seeds indoors to escape the bitter winter cold.

A gardener or farmer can sow directly into the ground with confidence that the seeds will be warm enough to germinate and grow.

If you happen to live in a region where your winters are mild enough that you don’t ever get a frost or freezing temperatures, you are very lucky!

For me, gardening sometimes feels like a race against the clock to see who will win, me or those drastic New England seasons.

PART I: Starting Seedlings Indoors

If you are like me and you have a winter that freezes the ground and produces frigid temperatures, you might start your onions inside from seed. Start your seeds about 8 to 10 weeks before your last frost.

If you choose this method, there are a few additional steps you must take to ensure a healthy and high-yielding onion crop. You will need a few extra things like seeding trays, and a good soil mixture.

I prefer using Pro-Mix BX, available on Amazon. This is a good all-purpose peat moss-based soil solution that has vermiculite added to it for good drainage, as well as perlite, limestone, and microscopic fungi that work in a symbiotic relationship with growing plants.

I find it to be a very adaptable growing medium that can handle a variety of plants and vegetable seeds.

Extra Strength 72 Cell and Flat Tray by Bootstrap Farmer

Regarding seed trays, they are easy to find at your local home center or online. You can buy traditional 6-packs, starting 2-4 seeds in each cell. Or you can buy plug flat trays.

A variety of these are available on Amazon, in different sizes depending on your needs. Again, you will place 2-4 seeds in each cell.

You can also use recycled containers from salad mixes or plastic take-home containers from your local deli, planting in rows of 7 to 10 seeds each. The choice is yours.

Fill your chosen trays with moistened soil, tamping down the soil just a bit. Seed 2-4 seeds in each cell. Water and set aside in a warm, well-ventilated location.

I have a greenhouse attached to the south side of my house, which enables me to have beautiful morning and afternoon light that keeps the soil warm and the seeds happy.

If you’re interested in building your own greenhouse, check out these DIY project ideas from some of our favorite bloggers.

EarlyGrow Medium Domed Propagator, available on Amazon

If you don’t have space for a greenhouse, consider buying plastic dome lids like the one pictured above to place over your trays, or using a seedling warming mat to help with propagation. Water whenever you notice that the soil looks dry.

When you notice germination, you need to be sure that your onions get enough light from that point on. Ideally, onions would like to have 12 hours of light and 12 hours of darkness per day.

During the winter when the sun isn’t particularly strong here in New England, I use fluorescent lights to keep my seedlings happy and healthy. Be sure to remove the dome and the warming mat, since your plants are now ready to grow on their own.

Photo by Leslie M.G.

Light hoods are easy to find in any hardware store, as are the accompanying bulbs. I prefer plant and aquarium fluorescent light bulbs, available on Amazon.

They produce a cool white spectrum light that is more conducive to the vegetative state of the plant, rather than a warmer yellow light reserved for flowering.

Once germinated, onions tend to grow quickly beneath lights. They will emerge from the soil and grow tall very fast, so it is important to monitor them.

When you notice that the onion seedlings are about 5 inches tall, take a sharp, clean pair of scissors and cut the tops off, leaving about 2 inches of the plant.

Cutting the tops will make your seedlings stronger and thicker, which will be beneficial when you are transplanting them into your garden.

Photo by Leslie M.G.

Also note that you can use these trimmings in salads, soups, or other dishes. They are delicious!

Hardening Off the Seedlings

Between propagation and transplanting lies hardening off. It is imperative to make sure that your seedlings will be strong enough to withstand lower temperatures, wind, and less frequent watering.

Now is the time to move your trays outdoors for periods of time, exposing them to the elements.

Put your plants outside in a protected spot during periods of more pleasant weather if possible, starting with a few hours during a sunny day and extending to an entire day. Do this for about a week, just before you are ready to transplant.

PART II: Planting Without Danger of Frost

If you do have mild seasons that allow for direct seeding without the threat of frozen ground or torrential rains and cold temperatures, then you don’t have to worry about starting onions indoors. Skip the seeds and consider planting onion sets instead.

Stargazer Perennials Mixed Onion Sets

Onion sets are smaller onion bulbs that were planted very thickly and never thinned out while they grew, to produce smaller, more hearty onion bulbs.

Harvested at the end of the summer and dried for approximately four weeks or more, these bulbs are stored until needed for the next growing season, when they will be ready for you to plant in your garden.

If you are going to be planting at all, figure out what hardiness zone you live in and plant accordingly. Based on your location, hardiness zones indicate when you can confidently begin to plant outdoors so that the plants will be able to withstand the minimum average temperature.

Knowing your hardiness zone is extremely beneficial for a gardener because it takes a lot of the guesswork out of the equation. Take the time to acquaint yourself with this USDA plant hardiness zone map to avoid making any mistakes in timing.

PART III: Planting Directly into the Soil or Transplanting from Indoors

Whether you are direct seeding onion sets or transplanting your seedlings, planting onions outside is a relatively simple process.

Transplant outdoors about 2-4 weeks after your last frost date. You will need a few tools, such as:

  • Spade or shovel
  • Stakes or long sturdy sticks
  • Twine or thin rope
  • Onion sets or seedlings

Though it’s not required, I prefer planting in rows. Decide how many rows you need to accommodate the number of onions you want to plant. You’ll want to allow for about 4-6 inches between seedlings, and 12-18 inches between rows.

Put a stake in the ground at either end of where you plan to place each row. Attach a piece of twine to a stick on one end, stretch it to the stick at the other end of the row, and anchor it.

The string and the stakes make it easy to dig a nice straight row, just by using the twine as a guideline.

Using a shovel or any other tool that will dig into the dirt, make your rows about 1-2 inches deep.

Sometimes I just bend down and drag my hand along the dirt just below each line of string, using my fingers to make a row. Sometimes I use the tip of a long-handled shovel or a spade. See what works best for you.

Sow directly into the soil, planting each onion set about 1 inch deep and 4 to 6 inches away from the next onion in the row. And be sure to leave 12 to 18 inches of space between each row to ensure a proper growing environment.

If you are transplanting your onion seedlings, you can plant 2-3 seedlings in a clump together, or you can choose to separate them and plant each one individually.

Some gardeners like to keep a few together, as they feel that it helps with growth. Others prefer to keep each one on its own. That’s your choice.

Do what feels right, and keep notes on your successes and failures from year to year. I group my seedlings together in groups of 2 or 3 and have great results.

Once you’ve planted all of the onions, cover up the rows with soil and tamp down lightly. Don’t push too hard. Everything that you plant in the garden needs some breathing room, even seeds.

Label your rows with garden stake tags, so you’ll know what’s there. You can find these at your local garden center, or they’re available on Amazon.

It’s a good idea to put the planting date on your tags as well, so that you have an idea of how long germination actually takes.

In addition to this, I keep a gardening journal from year to year, where I write down all of my planting dates. This is a great resource to have at the beginning of each growing season.

Part IV: Growing and Maintenance

Once planted, water your onions. You don’t need to soak them. You just want to make sure that the soil is dark and moist.

Water daily after you’ve planted until you see germination. After that, you can change your watering schedule to once or twice a week, depending upon how hot and sunny it is where you live.

If it is very dry, you’ll need to continue watering every day.

Just Add Mulch

Once they’re tall enough, you can place a thick layer of mulch around the plants to help retain moisture, and also to reduce the amount of weeding you will need to do.

I use straw because it locks moisture in and is seasoned enough so that I don’t have to worry about any insects that might be living in the medium, as you might find in hay grass. The last thing you want at this stage is to have to deal with unwanted insect visitors!

Keep in mind that onions need much more time to grow than some other crops, so you will be watering and weeding them quite a bit. Anything you can do to save time and be more efficient in your garden is a good thing.


Onions crave nitrogen, so fertilizing every two weeks with a high nitrogen fertilizer until the bulbs begin to form is vital.

Chicken manure works very well, as do other types of fertilizers that are nitrogen rich. Dr. Earth’s 9000 Nitro Big is a good option, available on Amazon.

Dr. Earth 9000 Nitro Big Fertilizer

Fertilization is a critical part of the process. Without enough nitrogen, your onions will not grow properly.

I mix my liquid fertilizer with water in a watering can and water each row by hand. It’s a rather meditative process, and I love doing it!

Continue to fertilize every two weeks until a few weeks before harvest. Onions appreciate the nitrogen throughout their entire growing cycle.

How Long Until Harvest?

Onions take about 3 to 4 months from planting to harvest. If you want spring onions, otherwise known as green onions, harvest them about 3 to 4 weeks after you’ve planted your sets.

Otherwise, be patient, water, fertilize, and weed. Before you know it, nice and plump onions will peek the crowns of their heads out of the soil to show you their progress.

Monitor them carefully, noticing when the long green tops begin to flop over and lay down, changing color from green to brown, indicating that it is harvest time.

The beautiful thing about onions is that once you plant them in the ground and they establish themselves, which can take about two weeks or so, you can pick fresh ones from that point on.

These spring onions have a lighter and sweeter flavor that’s wonderful in many recipes.

Otherwise, wait until you see large crowns popping out of the ground and you notice that the green onion tops are flopping over and beginning to brown. That is a sign that they are ready to be picked.

Part V: Harvest and Storage

Remove onions with your hands by pulling the long green and brown tops in an upward motion, from the ground to the sky.

At this point, you should not need any hand tools to help you with this process, as the onions are already halfway out of the soil and ready for removal.

Every once in a while, you might need a small hand spade to help. I like to keep one on hand, just in case.

Lay out to dry, keeping the long green tops attached.

Drying and Curing

When the weather is dry and sunny, many farmers and backyard gardeners will pull up their onions and leave them on top of the soil in rows for up to a week, allowing the sun and air to dry them naturally.

If you do not have such fantastic conditions, harvest your onions and bring them into a well-ventilated area like a barn or some kind of open room. Spread the onions out on a flat surface, like the floor or mesh drying racks, so that they can dry.

Either way, after a week or so, the onions will need additional time to continue drying. This process is called “curing,” and it is a critical step in the storage process.

If they are not properly cured, onions will not have a storage life at all, because the remaining moisture will cause them to rot.

After I bring my onions in from the garden, I like to lay a large canvas tarp on the floor of my garage and spread all of my onions out to cure. The canvas breathes and allows air to flow through, which is necessary for drying.

Some gardeners and farmers like to lay them on a barn floor or the floor of a garage or shed.

You can also dry your onions on a drying rack, which allows sufficient airflow all around the onions so that they can dry properly. This works well for a smaller harvest.

Many of my friends make their own drying racks and reuse them every year for many different crops throughout the season. They are great space savers and work very well.

Time to Store Your Harvest

You’ll know they are ready when you cut off a top and notice that there isn’t anything oozing from the cut.

If they aren’t dry enough, a milky white substance will seep out, telling you that the onions need more time and must continue to be cured. It is important that your onions be dry. Otherwise, the moisture inside will quickly rot your crop.

Once properly cured, you can begin the process of cutting off the tops, trimming the roots, and bagging your onions for storage. When cured and stored properly, some storage onions – such as Patterson or Red Wing – have a storage life of 6 months or more!

Dishing the Dirt

Gardening is cathartic and peaceful. A garden does not discriminate, nor does it turn its back on you. It soothes even the most savage of us on our worst days.

I go to the garden daily, often multiple times. It is my mediation and my therapy. I spend time walking down the rows, noticing the subtle differences of the plants.

Sometimes I take a glass of water and a book and sit in the garden for hours at a time, reading. Often, when friends come over, the first place they want to visit is the garden. Honestly, there is nothing quite like it.

Be thoughtful, plan ahead, and take your time. Be patient and vigilant.

Follow the basic guidelines outlined in this article, and you will have a beautiful crop of onions growing in your garden that you can enjoy, both fresh and for months to come.

Do you have any gardening secrets for growing onions? Any tips or ideas to offer? Add your comments below.

We’d love to hear from you!


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Greenhouse photos by Leslie M.G., © Ask the Experts, LLC. ALL RIGHTS RESERVED. See our TOS for more details. Product images via Stargazer Perennials, EarlyGrow, Bootstrap Farmer. Uncredited photos: .

About Leslie M.G.

Leslie M.G. is a lifelong lover of all things natural. She lives in rural southern Vermont with her wife, two dogs named Charlie and Ruby, and one sneaky little cat named Max. She is a grower, a farmer, a forager, and a writer who loves to combine all of these things to eke out a life in her little corner of the world. When the growing season comes to New England, her favorite thing to do is put on her overalls and head out to the garden, where she can plunge her hands into the rocky and fertile Vermont soil and get dirty. Her second-favorite thing to do? Pluck juicy ripe tomatoes from the vine and gobble them up, one by one.

No-Fail Tips to Growing Onions

Add delicious, savory flavors to cooked or raw dishes by growing your own onions.

Long-day onions take a long time—about five months—to grow from seed. Northern gardeners who want to grow onions from seed should consider growing short-day varieties or scallions (green onions).

Plant seeds in well-drained soil in full sun 1/2 inch deep, sowing one to five seeds per inch and thinning them as they grow. If you are growing onions to a large size, thin them so they are about 3 inches apart. For green onions, thin to 1/2 to 1 inch apart.

Keep the soil consistently moist when the green tops are actively growing.

How to Plant an Onion Bulb

If you want to grow large onions, it’s easiest to start with small bulbs, sold as transplants or sets.

If you’re growing sets into scallions or green onions, plant the bulbs 1-1/2 to 2 inches deep and 1 inch apart. If you’re growing large onions, plant the bulbs 1/2 inch deep and 4 inches apart. When to plant them depends on how soon you can work the ground in spring. Onions can survive light frost.

Keep onions moist until they reach the size you want and the green tops begin to tip over. When the soil dries out, dig up the bulbs and allow them to dry and cure in the sun (or a warm, dry, sheltered space if rain is forecast) for a week. This curing step helps the onions keep longer.

How Do Onions Grow?

Image zoom

Here’s something you might not know: Some onions need more daylight hours to grow than others.

Long-day onions stop growing their green tops and start forming bulbs when they receive 14 to 16 hours of light per day, making them a great choice for northern states (roughly the upper two-thirds of the United States, above the 36th parallel). In the Northern Hemisphere, the farther north you go, the longer the summer day length.

Short-day onions form bulbs when days contain 10 to 12 hours of sunlight, so they’re a good choice for planting in the spring and fall in the lower third of the United States.

Here’s another interesting tidbit: The ultimate size of an onion depends not only on the type it is, but the number and size of green leaves it forms. Each leaf indicates one ring of onion forming in the bulb below ground. The larger the leaf, the larger the ring is.

Onions grow their roots and leaves when temperatures are still on the cool side, 55 to 75 degrees F. When bulbs start to form, however, onions need warm temperatures and prefer low humidity. If there are a lot of cool, overcast days during a bulb’s growing period, onion growth stalls.

How to Grow Green Onions

Image zoom Greek onions

Growing green onions is easier than growing storage onions because the bulb doesn’t have to grow as much.

To grow green onions, you can plant any type of onion and simply harvest it when young. Or choose sets or seeds of bunching or scallion onions, which don’t form bulbs.

Plant seeds for green onions in full sun, placing them 1/4 inch deep and 1 to 2 inches apart in well-drained soil, thinning them as they grow. Harvest scallion onion plants by the time they reach about 10 inches tall. If you wait, the flavor becomes bitter as they grow larger.

How to Grow Onions and Garlic

  • By Deb Wiley

New! Click or tap the image to view the new Onion Growing Guide

By: Joseph Masabni

Yellow, white, and red/purple onions grow very well in Texas home gardens. Green onions may be eaten fresh or chopped and added to salads. Bulb onions may be sliced and used on sandwiches or dipped in batter and fried as onion rings. Although onions are a source of vitamins A and C, they are used mostly as a flavoring in other food dishes.


The varieties of onions that grow best in Texas are listed below.

Site selection

Onions grow best in full sunlight and well-drained soils.

Soil preparation

Work the garden soil only when it is dry enough not to stick to garden tools. Before seeding or transplanting, work the soil 8 to 10 inches deep.

Remove all rocks and trash from the soil; then break up the remaining clods and rake the soil smooth.


Onions are a cool-season crop and can stand temperatures well below freezing. They may be planted from seeds, from small bulbs called sets, or from transplants.

Seeding costs the least but takes longer before onions are ready. When seeding onions for bulbs, plant them ¼ inch deep during October through December. Place the seeds 1 inch apart. When the plants are about 6 inches high, thin them to one plant every 2 to 3 inches. Eat the extra plants as green onions.

If you use sets or transplants, plant them ¾ inch deep and 3 inches apart (Fig. 1). Do not transplant onions more than 1 inch deep.

Figure 1. Plant onion transplants or sets ¾ inch deep and 3 inches apart.


Onions grow best when the garden soil is fertilized correctly. Spread 2 to 3 pounds of a fertilizer such as 10-10-10 over a 100-square-feet of garden area. Measure and spread the fertilizer; then mix it with the top 3 to 4 inches of soil.


Watering once a week usually is enough in the spring. But you may need to water more often during dry, windy weather. Water onions slowly and deeply to help grow strong, healthy roots.

Care during the season

Weeds are easy to pull or cut when they are 3 to 4 inches tall. Do not let weeds or grasses grow large because they compete with onions for nutrients.

If you use a hoe to remove weeds and grass, do not chop too deeply. You may be cutting the onion roots. Pull all weeds by hand when possible.

When the onion plants have 5 to 6 leaves, apply fertilizer again to help grow larger plants and bigger bulbs (Fig. 2). Each leaf forms a ring in the onion bulb. More leaves means more rings and larger bulbs.

Use about ½ cup of fertilizer for each 10 feet of onion row. Scatter the fertilizer evenly between the rows. Water the onions after adding the fertilizer.

Figure 2. When the onions have 5 to 6 leaves each, scatter fertilizer around the plants and water it in.


Onions have few insect problems. However, thrips, which are very tiny insects, may be found between the center leaves.

Many insecticides are available at garden centers for homeowner use. Sevin is a synthetic insecticide; organic options include sulfur and Bt-based insecticides.


Diseases may be a problem on onions. Brown leaf tips or brown spots on the middle and lower parts of leaves may be caused by plant diseases.

Sulfur also has fungicidal properties and helps control many diseases. Neem oil and other fungicides are also available for use.

Before using a pesticide, read the product label. Always follow cautions, warnings, and directions.

Figure 3. Harvest bulb onions when the tops begin to fall over.


Onions seeded in October/December or transplanted in January/February should produce bulbs in May/July.

If used as green onions, they may be picked from the time they are pencil size until they begin to form bulbs.

For dry-bulb onions, let the plants grow larger. The onions are ready when the main stem begins to get weak and fall (Fig. 3). Pull the plants out of the soil.

Leave them lying in the garden for 1 to 2 days to dry. Then remove the tops and roots and let them keep drying in baskets or boxes.


Store onions in a refrigerator crisper or in a dry, airy place such as in a wire net in the garage or carport.

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Next to garlic, onions are one of the easiest things to grow. Requiring little attention they are a hardy plant that can and will do well in just about any environment. If you are a beginner gardener, learning how to grow bigger onions is a great way to get your feet wet.

Another plus is onions, once harvested, will last quite a while if stored correctly.

Whether you keep them in a cool dark root cellar, add them to canning recipes, or dice/slice and freeze, you can easily enjoy this harvest throughout the winter months.

With so many varieties and uses, onions are a staple in just about every home.

If you have never tried your hand at growing onions, I encourage you to follow these steps and give it a try.

How To Grow Bigger Onions – a Step by Step Guide

Prep your soil

I cannot stress enough how important this step is.

Why go to all the trouble of planting your seeds only to have unhealthy soil ruin your summer harvest? Take the time to prep your soil to ensure you have big healthy onions come fall.

Ninja Tip: Onions prefer Nitrogen-rich soil so keep this in mind when preparing to plant. You can purchase an inexpensive soil testing kit so you know just exactly what improvements your soil needs.

READ: Prepping Your Soil for a Successful Garden

Choose the best onion variety

With so many choices out there you can get lost deciding exactly what to plant.

I prefer the yellow and white variety onion and I have very good luck with these two each year. Choosing the right variety depends on where you live and what flavor you prefer.

My best advice is to try a few and see what you like.

This is a pretty thorough list that will give you an idea of what onion varieties are available.

Plant, set, or seed

Where I live sets work the best.

They are easy to plant and require less attention than seeds. The cost is still pretty low with this option, about $2 a pound which will give you approximately 100 or more sets depending on the size.

If you prefer the less costly seed option be prepared to do extra weeding since the seedlings can easily be crowded out especially in the beginning when they are small and fragile.

You can also start your seeds indoors and transplant when they are bigger.

Seeds need to be started about 6 weeks prior to outside planting and hardened a few days to acclimate them to your weather.

Read: How to Start Seeds Indoors

Plant at the right time

Here in Pennsylvania, I have found it is best to plant onions just as soon as you can work the ground which for us is late March or early April.

If you miss your window to plant, don’t worry you still can. I have planted as late as June and have been fine. Just know that the later you plant the later your harvest will be.

The trick is to harvest before the weather gets too cold in fall. Be aware that since you will have a shorter growing time, you may also have smaller onions.

If you plant a large number of onions, it is best to stagger your plantings. This way you will have a steady stream of ripe onions come fall. To do this plant your first row of onions then plant additional rows each week until you are completely planted.

Plant in raised rows

Our entire property is wet, really really wet.

I experimented a few years ago by planting my onions in raised rows and my onions were huge! I was so impressed with how well they did, that I now plant most of my veggies this way.

Be sure to space your onions 4-5″ apart and plant sets or plants at 1″ deep. I also keep my rows at 18″ apart.

When growing onions this spacing allows enough room for me to get down the rows without risking injury to my plants, yet not so much room that I am wasting valuable garden space.

Mulch to deter weeds

Since onions require very little attention, mulching well is important.

I used to forget about my onions giving my best care to my delicate tomato and pepper plants. When it came time to harvest my poor onions would be lost in a sea of weeds. Because the weeds stole all the nutrients from the soil my onions would be small and soft.

To mulch simply lay a layer of newspaper down on the ground and cover with cut grass or straw. The newspaper will naturally compost down as the growing season progresses and will act as a barrier limiting the number of weeds that will grow.

Now that I am mulching my raised onion rows, I only need to weed around the very base of each plant. A weedless onion is a happy onion.

It just amazes me how a little time in March can make all the difference come September. 😉

Ninja tip: Be careful when weeding so you do not accidentally pull out your onion plant.

Read: How to Mulch Your Garden

Water your onions correctly

This can be a bit tricky.

Water too much and you will encourage diseases. Water too little and you will produce small and weak plants.

Mulch is also very helpful with watering, it ensures better drainage and keeps the soil moist longer.

Ninja tip: if you want a sweeter onion, water more steadily. Be sure to keep water off of the leaves since this can promote fungal diseases. A soaker hose is a perfect option for this. Drought onions tend to be a bit pungent so keep this in mind when growing.

Cover or not to Cover

As your onions grow they will emerge from the ground exposing part of the onion. At this point, I would not cover your onions with soil.

I was told to do this once and my onions were small and soft.

Leave your onions as they are.

Diseases to watch for

The biggest problem I have had with my onions is bolting.

Bolt is when an onion produces a flower and this is bad news for the onion. This can occur especially if the growing season is wet or chilly.

If you see an onion bolt, it is best if you remove the stalk and the flower.

More often than not, once an onion bolts the bulb is done growing. Don’t worry though. You can harvest your bolted onion, dry and use as you normally would. They may be small but will taste just fine.

You can also choose to leave the onion in the ground, but this is not always the best way to go since I have found the taste to be just a bit “off” when I do this. If you have a recurring problem with bolting onions, look for heat treated sets next planting season. I have not tried these but have heard good things.


When your onion tops begin to yellow and fall over that means your onions are just about ready for harvest.

You can encourage things by bending your tops over and even loosening the soil around the bulb just a bit. After a few days, pull your onions and let them dry on the ground where they are.

Dry and store

Pick all your onions shaking off excess dirt as you go. Let your onions sit until the tops are brown and dry. This should take 1-2 weeks.

I have found an old window screen works perfectly for this. I also have a plastic grate tray that works as well.

Once you are sure your onions are dry, remove tops and roots with scissors. I like to remove the outer skin especially if it is brittle and dry. This just keeps things a bit neater in my pantry.

You can store your onions in mesh breathable bags in your root cellar or pantry if you intend to use them up quickly. Check your supply each week for any onion that is beginning to go bad.

Onions will last 2-3 months in a pantry and 5-8 months in a cool dry root cellar.

Freezing onions

Another storing option is freezing.

If you plan to freeze your onions make sure you dice them or slice them before you do. Place your cut onions on a foil covered cookie sheet and par-freeze first.

Once frozen you can put into labeled freezer bags being sure to remove as much air as you can before your final freeze. By doing this you will keep your onions from getting freezer burn or freezing in a hard chunk.

Whether you are beginning your first garden or a seasoned pro, onions can be a great addition.


Variety Selection

The size of the onion bulb is dependent upon the number and size of the green leaves or tops at the time of bulb maturity. For each leaf there will be a ring of onion; the larger the leaf, the larger the ring will be. The onion will first form a top and then, depending on the onion variety and length of daylight, start to form the bulb. Onions are characterized by day length; “long-day” onion varieties will quit forming tops and begin to form bulbs when the daylength reaches 14 to 16 hours while “short-day” onions will start making bulbs much earlier in the year when there are only 10 to 12 hours of daylight. A general rule of them is that “long-day” onions do better in northern states (north of 36th parallel) while “short-day” onions do better in states south of that line. See the onion information resource page for more detailed variety descriptions and photos.

Onions From Seed

Mid to late October is the best time to plant seed of the super sweet, short-to-intermediate daylength onion types in Texas zones III – V (USDA Zones 8 and 9). Seeds can be sown directly into the garden, covered with one-fourth inch of soil and should sprout within 7- 10 days. If planted thickly, plants can be pulled and utilized as green onions or scallions for salads or fresh eating in 8-10 weeks. However, most gardeners want to grow an onion bulb as large as a basketball. To do this, the onion plants must be thinned by next February until they are at least 2-3 inches apart to insure adequate bulb expansion. The removed plants can be used for scallions or for transplanting into another area of the garden so that these too will have adequate space in which to enlarge into large bulbs.

Fertilization of onion plants is vital to success. Texas A&M research findings indicate that onion growth and yield can be greatly enhanced by banding phosphorus 2-3 inches below seed at planting time. This phosphorus acts as a starter solution which invigorates the growth of young seedlings. Banding phosphorus, such as super phosphate (0-20-0), 2-3 inches below the seed involves making a trench 3 inches deep, distributing one-half cup of super phosphate per 10 row feet, covering the phosphate with soil, sowing seed and covering lightly with one-half inch or less of soil. Once established, onion plants should receive additional amounts of fertilizer (21-0-0 – Ammonium sulfate or Ammonium nitrate) as a side-dress application every month.

Gardeners who tend to procrastinate should be warned that planting later than October could mean failure. Failure in onion production comes in two forms – – complete annihilation of the young seedlings during a cold winter or an abundance of spring onion flowers which decrease bulb size, weight and storage ability. Onion plants which are small and rapidly growing when the cold temperatures of winter arrive will probably not survive. Yet, if you plant earlier and the stem of onion plants are larger than a pencil when exposed to cold temperatures, the onion will initiate and produce a flower during the following spring. This flowering is termed bolting. Bolting requires low temperatures. Most rapid bolting is caused by temperatures of 40-45 degrees F. or below. Fall seeded crops are susceptible to bolting the following spring if warm fall temperatures, allowing excessive growth, are followed by low winter temperatures and slowed growth. Many gardeners believe that early removal of the onion flower stalk will cause onion bulb enlargement but this has not proven to be the case. Flowering causes a decrease in bulb size as well as a central flower stalk which enhances decay during storage. This is exactly what will happen to those who are planting onion transplants or sets in October or November with the hope of large onions next spring. The onion bulbs which produce a flower stalk may be large but they will be light-weight (one-half the weight of a comparable size, non-flowered onion bulb) and prone to decay. Obviously, what you see is not always what you get! The best way to insure success is to either plant the onion seed from October 1 until November 15 or plant transplants from January through February in Texas Zones III – V (USDA Zones 8 and 9).

Care Of Transplant Instructions

When you receive live plants, they should be planted as soon as possible. Should conditions exist that make you unable to plant these plants right away, remove the onion plants from the box and spread them out in a cool, dry area. The roots and tops may begin to dry out but do not be alarmed, the onion is a member of the lily family and as such will live for approximately three weeks off the bulb. The first thing that the onion will do after planting will be to shoot new roots.

Preparing the Soil

Onions are best grown on raised beds at least four inches high and 20 inches wide. Onion growth and yield can be greatly enhanced by banding a fertilizer rich in phosphorous (10-20-10) 2 to 3 inches below transplants at planting time. Make a trench in the top of the bed fours inches deep, distribute one-half cup of the fertilizer per 10 linear feet of row, cover the fertilizer with two inches of soil and plant the transplants.


Set plants out approximately one inch deep with a four inch spacing. On the raised bed, set two rows on each bed, four inches in from the side of the row. Should you want to harvest some of the onions during the growing season as green onions, you may plant the plants as close as two inches apart. Pull every other one, prior to them beginning to bulb, leaving some for larger onions. Transplants should be set out 4 to 6 weeks prior to the date of the last average spring freeze.

Fertilization and Growing Tips

Onions require a high source of nitrogen. A nitrogen-based fertilizer (ammonium sulfate or ammonium nitrate) should be applied at the rate of one cup per twenty feet of row. The first application should be about three weeks after planting and then continue with applications every 2 to 3 weeks. Once the neck starts feeling soft do not apply any more fertilizer. This should occur approximately 4 weeks prior to harvest. Always water immediately after feeding and maintain moisture during the growing season. The closer to harvest the more water the onion will require. For weed control a pre-emergent herbicide (DACTHAL) should be applied prior to planting. This will provide weed control for approximately one month after planting. Other products such as GOAL and BUCTRIL, can assist in weed control during the growing season. Always follow label instructions. For organic gardeners a rich compost high in Nitrogen should be incorporated into the soil. Unfortunately, there is not any product available to assist in weed control so the only method will be cultivation. While cultivating be careful not to damage the onion bulb. As the onion begins to bulb the soil around the bulb should be loose so the onion is free to expand. Do not move dirt on top of the onion since this will prevent the onion from forming its natural bulb. Start early with cultivation practices.

Disease and Insect Control

The two major diseases that will affect onions are blight and purple blotch. Should the leaves turn pale-green, then yellow, blight has probably affected the plant. Purple blotch causes purple lesions on the leaves. Heavy dew and foggy weather favor their rapid spread, and when prolonged rainy spells occur in warm weather, these diseases can be very destructive. The best cure is prevention: use only well-drained soil, run the rows in the same direction as prevailing wind and avoid windbreaks or other protection. Should conditions persist, a spray with a multipurpose fungicide such as daconil can be applied on a 7 to 10 day schedule.

The insect that causes the most damage is the onion thrip. They feed by rasping the surface of the leaves and sucking the liberated juices. They are light-brown in color and are approximately 1mm long. The most available insecticides are Malathion or Diazinon, or an insecticidal soap or biological insecticide may be used. Do not apply any insecticide within seven days of harvest and always follow label instructions.

Flowering — Abnormal For Onions; Normal For Garlic

Most folks want to grow onion bulbs NOT onion flowers! What causes bulb onions to send up flower stalks? Flowering of onions can be caused by several things but usually the most prevalent is temperature fluctuation. An onion is classed as a biennial which means it normally takes 2 years to go from seed to seed. Temperature is the controlling or triggering factor in this process. If an onion plant is exposed to alternating cold and warm temperatures resulting in the onion plant going dormant, resuming growth, going dormant and then resuming growth again, the onion bulbs prematurely flower or bolt. The onion is deceived into believing it has completed two growth cycles or years of growth in its biennial life cycle so it finalizes the cycle by blooming. Flowering can be controlled by planting the right variety at the right time. Use only transplants that are pencil-sized or smaller in diameter when planting in early spring or always plant seed, NEVER transplants, in early fall in Texas Zones III – V (USDA Zones 8 and 9).

DON’T plant garlic in the spring! Bulb formation in garlic occurs in response to the lengthening days of spring, and bulbing and maturity are considerably hastened if temperatures are high. In addition to these requirements, the dormant cloves (divisions of the large bulb) or young growing plants must be exposed to cold temperatures between 32 and 50 degrees F. for one or two months in order to initiate bulbing. Plants that are never exposed to temperatures below 65 degrees F. may fail to form bulbs. With fall plantings, the cold treatment is accomplished quite naturally throughout the winter, but a spring planting spells disaster in Texas Zones III – V (USDA Zones 8 and 9)

What To Do About Flowering?

What can one do if flower stalks appear? Should the flower stalks be removed from the onion plants? Suit yourself but once the onion plant has bolted, or sent up a flower stalk, there is nothing you can do to eliminate this problem. The onion bulbs will be edible but smaller. Use these onions as soon as possible because the green flower stalk which emerges through the center of the bulb will make storage almost impossible. Seedstalk formation (bolting) of garlic is not induced by exposure to fluctuating temperatures, as is the case with onions, which means that a wide range of fall planting dates is permissible for this crop. Seedstalk formation is also not damaging to garlic since the cloves are arranged around the seedstalk and will be removed from the dried seedstalk. Conversely, the edible onion bulb is penetrated by the seedstalk which is hard when the bulb is harvested, but prematurely decays causing loss of the entire bulb in storage. When the tops become yellowish and partly dry, garlic is ready for harvest.

Harvesting And Storage
Onions are fully mature when their tops have fallen over. After pulling from the ground allow the onion to dry, clip the roots and cut the tops back to one inch. The key to preserving onions and to prevent bruising is to keep them cool, dry and separated. In the refrigerator, wrapped separately in foil, onions can be preserved for as long as a year. The best way to store onions is in a mesh bag or nylon stocking. Place an onion in the bag and tie a knot or put a plastic tie between the onions and continue until the stocking is full. Loop the stocking over a rafter or nail in a cool dry building and when an onion is desired, simply clip off the bottom onion with a pair of scissors or remove the plastic tie. Another suggestion is to spread the onions out on a screen which will allow adequate ventilation, but remember to keep them from touching each other. As a general rule, the sweeter the onion, the higher the water content, and therefore the less shelf life. A more pungent onion will store longer so eat the sweet varieties first and save the more pungent onions for storage.


Onion Info – Tips For Growing Big Onions

According to most onion info, the number of leaves the plant produces before the days get shorter determines the size of the onion. Therefore, the earlier you plant the seed (or plants), the bigger the onions you will grow. If your onions won’t grow big, keep reading for more onion facts that can help you fix that.

Facts About Onions

Onions are good for us. They are high in energy and water content. They are low in calories. Onions increase circulation, lower blood pressure, and prevent blood clotting. The list of onion facts can go on and on; however, one of the most important facts about onions is how to grow them.

Growing Onion Info

Onions can be grown from seeds, sets, or plants. Seeds develop in summer once flowers cease blooming. Seeds can be sown directly in the garden in very early spring, with onion plants ready for harvest by late summer/early fall.

Onion sets, which are grown from the previous year’s seed, are usually about the size of marbles when harvested and stored until the following spring, when they can be planted.

Onion plants are also started from seed but are only about the size of a pencil when they are pulled, at which point, the onion plants are sold to gardeners.

Sets and plants are generally the most popular methods of growing onions. Common onion info tells us that it is often easier growing big onions from plants than from seed.

Help, My Onions Won’t Grow Big – Growing Big Onions

It is just one of those onion facts that the key to growing big onions is early planting, with fertilizer or compost. Seeds can also be sown in trays and left in a cool location until the seedlings reach about 1-2 inches tall, at which time they can be placed in deep biodegradable pots filled with loose, composted soil.

Place seedlings at the top and keep pots somewhat dry to encourage more extensive rooting as they move down in search of moisture. Plant the pots in the garden in early spring, and as they absorb moisture from the soil, they will eventually decompose, encouraging a secondary root system near the soil surface, which will produce larger onions.

Onion sets and onion plants require loose soil and should be planted early (end of February or March). Dig a shallow trench, working in compost or fertilizer for big onions. Likewise, raised beds can be implemented. Plant the onions about an inch deep and 4-5 inches apart.

Wider spacing makes it easier to control weeds, which can compete for nutrients. Keep the area weed free; otherwise, the onions won’t grow big. Once onion bulbs begin to swell (in late spring), ensure that they remain above ground. Onion plants will continue to increase in size until the middle of summer, at which time their tops begin to fade. Once these tops have completely faded and fallen over, onion plants can be pulled and left in the sun to dry for several days before storing in a cool, dry area.

Growing onions doesn’t have to be frustrating. Start them early, follow the above big onion facts and remember to add compost or fertilizer for big onions.

There’s an onion for nearly every taste and culinary purpose: mild to pungent, tiny pearl onions to big Bermudas. Home gardeners get a choice in how they plant onions, too, with popular methods including sets, transplants, and seeds. Some even employ all three methods under the theory that you can’t have too many onions!

First, find out which varieties do best in your region. Since the lengthening days of late spring trigger the transition from growing leaves and roots to the business of forming bulbs, the types of onions that succeed in Northern states differ from those in the South.

Seed packets and catalog descriptions should reveal which varieties work well in short-day regions (those that form bulbs when day length is only 10 to 12 hours), intermediate-day regions (12 to 14 hours), or long-day regions (14 to 16 hours). A few onions are considered day-neutral and can grow anywhere.

Dixondale Farms, which grows and sells onion transplants, provides this map to aid in variety selection. Note the area of overlap between long-day and intermediate-day regions where varieties of either type can grow and a similar overlapping area for intermediate-day and short-day varieties. Canadian gardeners should select long-day varieties.

Once you’ve found the right type for your garden, here’s how each planting method works and how to get started:

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