How to Plant Green Onions: 6 Vital Tips

Green onions make an excellent addition to your home veggie garden. Plant these easy-to-grow veggies just about anywhere, from a traditional garden or raised bed to a pot on your kitchen windowsill. Let’s find out how to plant green onions for a continuous supply at any time of the year.

Allium fistulosum is a perennial member of the onion plant family. Sometimes called bunching onions, scallions, or spring onions, the plants form a large clump of long, green, edible leaves with small bulbs. They’re related to bulb onions, chives, garlic, leeks, and shallots. Another form of green onions consists of immature regular onions (Allium cepa) harvested before a mature bulb forms.

Green onions make fantastic companion plants for many other fruits and veggies. They don’t take up much garden space and repel a wide variety of commonplace pests.

With an exceptionally quick growing season, green onions are ready to harvest within 20-30 days from planting seeds. Read on to discover everything you’ll need to know about planting green onions in your home garden.

What to Know About Planting Green Onions

How to plant green onions depends on which variety you choose and the environmental conditions in your garden space. When growing perennial scallion plants, find a location where they can remain undisturbed for many years. They’re hardy in USDA planting zones 5-9, and numerous varieties can withstand temperatures down to -10℉.

Whether you’re growing green onion plants indoors or out in your garden, make sure they get six or more hours of direct sunlight through the day. They grow best when the soil contains plenty of organic matter and stays consistently moist but never soggy.

Make the most of your kitchen scraps and regrow green onions from the root end for an easy, fun DIY project. Cut the stem where it turns white and place it in a shallow dish with just enough fresh water to cover the roots. Set it on a sunny windowsill, and you’ll see new green shoots emerge within a few days. Replace the water every day or two. You can typically get three or four more harvests from the small bulbs.

Growing Green Onions from Seed

If you’re direct-sowing green onion seeds, plant them a quarter-inch deep and lightly top-dress them with a mixture of garden soil and compost. It’s beneficial to pre-moisten the ground to avoid displacing the tiny seeds.

For starting green onion seeds indoors, begin by filling a seedling tray, peat pots, or a repurposed cardboard egg carton with seed-starting potting mix. Moisten the potting soil, then sow groups of three or four seeds a quarter-inch deep.

Green onion seeds usually take one to two weeks to germinate. The seeds will germinate in soil as cold as 40℉, albeit much more slowly. The optimal soil temperature for germination is 60-75℉.

Another approach to planting green onions is to use onion sets. They’re typically Allium cepa or bulb onions and should get harvested after about 6 weeks while they still have small bulbs. Plant your onion sets an inch to an inch and a half deep and close enough together to touch.

When to Plant Green Onions

Many gardeners ask, “What month do you plant green onions?” The best time for planting green onions is generally in the early spring, as soon as you can work the soil. They’re also a fantastic fall crop and grow through the winter in mild climates. Since green onions grow so quickly, most growers direct-sow seeds in the garden bed or container.

Sow seeds around your area’s usual last frost date for a springtime crop. In the autumn, plant green onion seeds four or five weeks before your intended harvest date.

Ideal Growing Conditions

Green onions are easy and rewarding to grow in a wide variety of conditions. While they grow best in full sun, the plants also tolerate partial shade. Green onions prefer a neutral to slightly acidic soil pH level, between 6.0 and 7.0.

Add a generous amount of organic compost in early spring to refresh your garden soil. It’s also helpful to warm the soil by covering your planting area with dark-colored mulch or black plastic a week or two ahead of planting. Doing so helps seeds germinate faster.

Give green onions around an inch of water per week and more during especially hot or dry weather. The plants have shallow root systems and suffer when competing for nutrients and water with weeds. Be careful when weeding to avoid causing accidental damage.

Mulching helps insulate the soil, minimize weed growth, and retain moisture. Use organic material like dry leaves, grass clippings, pine needles, straw, or bark mulch.

Onion plants are heavy feeders. For the best possible results, give them organic, high-nitrogen fertilizer throughout the growing season.

How to Plant Green Onions in Pots

If you don’t have an outdoor garden space at home, don’t worry. Growing green onions in a container garden on your patio, porch, or even a sunny windowsill is also possible.

Use potting soil that’s rich in nutrients and drains well. Look for soil blend with added perlite for drainage, compost or fertilizer for slow-release nutrients, and peat moss or coconut coir for balanced moisture retention.

It’s essential to fertilize your container-grown green onions regularly. Plants use up water and fertilizer much faster when growing in containers instead of in the ground.

If you’re using liquid fertilizer, apply it every two to three weeks. For granular fertilizer, applications should get spaced five or six weeks apart.

Harvesting and Storing Homegrown Green Onions

There are a few options for harvesting green onions. You can begin collecting the leaves once they’re at least six inches long. Or, harvest the whole plant after four to six weeks if you’d rather use the small bulb and white stalk as well as the leaves.

Snip the leafy green tops as needed throughout the growing season for salads, soups, and garnishes. To keep your plant growing, don’t cut more than a third of the leaves at one time and leave several inches at the bottom to encourage rapid regrowth.

Harvest the entire green onion by gently loosening the soil around the plant’s base. Pull up the whole plant or carefully separate a few stalks from the central cluster and replant the rest.

Keep your green onions fresh by storing them wrapped in a damp paper towel inside a plastic bag in your refrigerator’s crisper drawer. They’ll last for up to two weeks when stored properly.

Troubleshooting Common Pest and Disease Problems

Green onions are usually quite simple to grow. However, they occasionally suffer from a few common pest and disease issues. Healthy plants are more resilient against attacks by insects or pathogens. Getting appropriate amounts of light, water, and fertilizer is their best defense.

Aphids, onion maggots, leafminers, and thrips are some of the most frequent insect pests that feed on green onions. Cover young seedlings with floating row covers to keep insects from laying eggs on them in the springtime. Also, cedar mulch wards off numerous insect pests, including aphids, mosquitoes, thrips, and ants. To deal with a pest infestation, spray all parts of the plants with an organic pesticide like insecticidal soap, horticultural oil, or neem oil.

Downy mildew is a widespread fungal disease that reproduces quickly in persistently damp conditions. The leaves develop yellow and brown patches on their upper surfaces. Eventually, darker spots form with fuzzy brown, grey, or purple fungal spores on the leaves’ undersides. Make sure that your plants have adequate air circulation and let the soil dry out between watering. Treat affected plants with an organic copper or sulfur fungicide.

Growing green onions from seed is well worth the effort. Homegrown veggies are tastier and more nutritious than what’s available at the supermarket. You can enjoy a generous harvest of fresh green onions in just four to six weeks. All that’s required is consistently moist soil, nitrogen-rich fertilizer, and four to six hours of bright light daily. Harvest the leafy green tops as needed, or dig up the entire plant to use the small bulbs and white stalks.

Do you have any questions or suggestions about how to plant green onions? Please share them in the comments! If you found these gardening tips helpful, please feel free to share this post about growing green onions with your plant-loving family and friends.