There’s no denying that scallions, bunching onions, and green onions make any dish more delicious!
The mild and sweet onion flavor of the bulbs makes them perfect for eating raw in salads or cooked in chowders, soups, stir-fry, and any recipe that calls for onions. Add a splash of green to your dish by using greens as a garnish.
If you find yourself constantly buying fresh green onions at the grocery store, they can really start to add up over time. Try to keep some around the kitchen instead so that you have them on hand when you need them. You can grow an unlimited supply of green onions that will last you throughout the year by learning how to properly cultivate them.
About Green Onions
Green onions are an evergreen perennial crop originally native to Asia. They are also referred to as bunching onions, spring onions, scallions, and Welsh onions. Slender onions with long, flavorful green leaves, scallions don’t form rounded bulbs like regular onions. They have a mild onion flavor and can be eaten raw.
Green onions are very rapid growers, as opposed to bulb onions. It only takes 50 to 60 days for an onion to grow from a seed to a harvestable size, whereas regular onions take between 100 to 175 days to mature. They are not daylight-sensitive either. This means that you can plant seeds at any time during the year.
Perennial green onions can be grown in USDA zones 6 through 9 where the climate is typically warmer and winters are mild. The entire green onion is edible, including the flowers.
Types of Green Onions
There are many types of green onions, some of which can withstand cold weather, some with red skins, and some that mature quickly. All grow mild-flavored bulbless straight stalks and green foliage. Here are some types of green onions (Allium fistulosum) to consider:
- Crimson Forest Scallions have bright green foliage and a deep red stem that adds a nice pop of color to salads and stir-fries. The red color gets lighter when growing in warm temperatures. This heirloom variety is ready to harvest in 60 days.
- Evergreen Long White bunching onion is one I have relied on for many years. It is an heirloom variety that produces a long white bulb and 14-inch tall green stalks. Start seeds early, and it is ready to harvest in about 30 days after transplanting and 60 days for direct sowed seeds. Evergreen is very cold-hardy and overwinters very well.
- Ishikura Bunching Onions is a Japanese variety that can grow up to two feet tall. It will develop longer white bulbs by mounding the soil up around the plant as it grows. Plant this variety early and begin harvesting in about 50 days. This tender and tasty scallion is also heat tolerant and can be overwintered.
- Parade Bunching Onions is an open-pollinated variety that grows uniform-sized upright plants with white stems and dark green foliage. The crisp and mild scallions are ready to harvest in 70 days.
- Tokyo Long White is a Japanese scallion with long, slender, and mild-tasting bulbs and blue-green tops. If you mound the soil as the scallions grow, it will produce a long white stalk. Grow Tokyo as an annual because this variety doesn’t overwinter very well, but it will withstand heat like a champ and matures in 65 days.
- Warrior Bunching Onions is a quick-growing scallion that produces uniform slender white stalks and deep green leaves. If you start seeds indoors, Warrior is ready for harvesting in just 30 days after transplanting into the garden and direct sowed seeds in 60 days.
Planting Green Onions
You should start planting your seeds indoors 8 to 10 weeks before the last frost of the year. To ensure that your seeds germinate, water them regularly and sow them at a depth of 1/4 inch when the temperature is at least 50 degrees Fahrenheit. A seedling heating mat can help with germination. Space the seedlings out so they are 2 inches apart, or wait until they start to separate on their own.
Divide the seedlings when they are ready to be transplanted. Plant 2 to 4 weeks before your last frost date in the spring, but you can keep planting throughout the spring and summer seasons and into the fall if desired. Plant your seedlings one to two inches apart in rows spaced six inches apart. Green onions may help to keep pests away from your other crops if you plant them together. Be sure to water your onion plants regularly as they have shallow roots.
You should plant your traditional onion sets two to four weeks before the last frost date. This will give them enough time to grow before the frost hits. Be careful with them as if they were transplanted green onions, but plant at the very least 2 inches apart to allow for the bulbs to grow. You can use the green leaves of the Allium cepa in the same way you would use green onions, but the Allium cepa will eventually form a larger onion bulb.
Now that you know more about the types of green onions, you can learn how to take care of them so they can mature! What are some specific things you should do to care for scallions?
Sun and Temperature
Put your plant in a place where it will get a lot of sun. It should get at least six hours of direct sunlight every day. Scallions will grow best in zones 6-9, and they prefer temperatures that are between 60-75 degrees Fahrenheit. You can protect your scallion bulbs from the cold by mulching them with straw or other organic matter in the fall. This will also help prevent weeds.
If you are living in an area that is warmer than 9 degrees, it is recommended that you plant your green onions in a location of the garden that provides them with shade during the afternoon hours. You can absolutely grow scallions in warm climates! They love full sun.
Growing green onions indoors is an option for those who have cold winters. Be sure to give them lots of light and warmth during the cold season and you’ll be able to harvest scallions all winter and well into spring.
Water and Humidity
The best time to water your plants is in the morning hours, as this will reduce the amount of moisture that is lost through evaporation. The leaves of the plant are able to dry out during the day, which makes the plant less likely to develop diseases.
Scallions are sensitive to drought. Aim for 1 inch of water per week. Use soaker hoses or drip irrigation. Ditch or “furrow” irrigation is another viable method. Dig a long, shallow trench next to your plants. Fill the trench with water, and let the bulbs soak up the moisture.
Sandy soil will require more irrigation than other types of soil. Plants grow more slowly in cooler weather, so they need less water.
Scallions prefer fluffy, well-balanced, and loamy soil. This will help to improve the drainage, aeration and nutrient content of the soil. At least six inches of organic matter like compost should be added to poor soil to improve drainage, aeration and nutrient content. Onion bulbs struggle to develop in clay soil that dries out or holds too much moisture. You should amend your soil to improve drainage while still keeping the moisture levels high.
To grow scallions, the best soil pH is between 6.0 and 7.0. You can plant these bulbs near tomatoes or other solanaceous plants without worrying about the soil pH being too low. If the soil is too alkaline, these plants may struggle to get off to a good start.
Scallion plants are leafy greens, so it is important to fertilize them regularly with a nitrogen-rich amendment. Liquid fertilizers such as fish fertilizer or comfrey tea are rich in nutrients and can help your plants during the growing season. A long-term solution is to use granular fertilizers that will release slowly into the soil. When searching for a fertilizer, look for one that is high in nitrogen. Nitrogen is represented by the “N” in N-P-K. If desired, top-dress with rich compost.
Most of the time, pruning is done only to harvest the plant. Plants can be trimmed for cosmetic purposes, such as the removal of wilted leaves, but otherwise should be left until the plant is no longer producing fruit.
To prevent your green onions from bolting to seed, trim off the flower stalk. You may often experience leaf wilt during flowering. Trimming the bud and stalk early will redirect the plant’s energy towards leaf development.
Then, wait until the seed pod dries out and turns brown. To collect seeds, you should allow the flowers to fully open, and then wait until the seed pod dries out and turns brown. Onion flowers are pretty impressive. They create a large, almost ball-shaped umbel. Tie a paper bag over the top of the flower and tightly secure it to the stalk when it starts to fade. The seeds are very tiny. Cut the plant’s stalk when it starts to sag, and set it in a location where the head can dry out and the seeds can fall from the flower.
One method of propagation is bulbs or “sets”. The best time to plant sets is in late fall, and they can overwinter in the garden. In the spring they’ll start pushing up new growth.
If you start with young Allium cepa plants, you can get green onion stalks. If you want to grow tree green onions, make sure you plant Allium fistulosum, as this is the only type of onion that doesn’t produce an onion bulb. The scallion, also known as the green onion, has a milder flavor than the regular onion.
If you want to regrow green onions, you can save the bulbs from store-bought ones. If you take care of them, they will produce tall green leaves every couple of weeks and also provide you with a bonus crop. You can grow green onions indoors or outdoors by putting the onion bases in moist soil and under a T5 light. The onions will grow rapidly.
And growing your plants from seeds is definitely an option. There are many different types of seeds available for different species of scallions or bunching onions. To plant the seeds, follow the directions in the “planting” section.
When and How to Harvest
You can harvest green onions approximately 30 days after transplanting them, or after 60 days if you want them to be more mature in size.
The best time to harvest the bulbs is when they have turned white and are the same thickness as a pencil. To achieve a milder onion flavor, use thinner onions. If you want a more robust flavor, use thicker, more mature onions.
One of the best things about green onions is that they never stop growing. The greens on the end of the stem continue to get larger and produce fresh greens. Don’t harvest your vegetables until you are ready to eat them.
You can get what you need by digging up the whole plant, or just cutting a few from the outside. The plant will regrow more greens.
Storing Green Onions
While your green onions are still wet from harvesting, rinse them well under clean running water. After rinsing, allow them to air dry. Wrap the celery stalks in a paper towel, and place them in a plastic zipper bag or reusable container. Store the celery in the crisper drawer in the refrigerator. The paper towel will prevent the green onions from becoming slimy by absorbing moisture. If you store your green onions properly, they can last for up to a week in the fridge.
To preserve the delicious flavor of green onions, freeze them; however, their texture will soften when thawed. Make sure your green onions are clean and dry before freezing them.
I like to chop my green onions and keep them in a sealable freezer bag in the freezer. I only take out the amount of parsley I need when I’m going to use it as a garnish. I put the rest away. Very convenient!
If you own a dehydrator, you can dry your extra green onions until they are so dry that they snap in half easily. To create green onion powder, first chop the scallions then grind them in a food processor.
Troubleshooting Growing Problems
Although scallions are generally a healthy crop, several pests and diseases common to most allium crops occasionally affect the plants:
- Common pests include bulb mites, cutworms, leaf miners, onion maggots, and onion thrips. While a severe infestation will ruin the crop, most pests that feed on the leaves won’t kill the plants, but they may destroy some of the foliage and spread fungal diseases. You can use row covers to prevent the pests from finding your plants. If you do see signs of damage, remove the affected leaves.
- The most common diseases that affect onions include botrytis, downy mildew, pink root, purple blotch, and white rot. Once infected, the disease will kill your onions. Destroy any infected plants and avoid planting alliums in that garden bed for at least 2 years. To help prevent fungal diseases, improve airflow by adequately spacing the plants, controlling weeds, and growing in healthy soil that drains well in full sun to partial shade.
Frequently Asked Questions
Q: Do green onions grow better in water or soil?
Q: Can you regrow green onions in water? A: Yes, but the roots won’t have access to nutrients or oxygen, so they won’t be able to survive for very long. The soil will provide the nutrients they need.
Q: Do green onions grow back every year?
B: Green onions are a type of onion that is grown for its greens, and they can live for several seasons. The flowers will come back after being cut down, but they won’t regrow if the bulbs die or are frozen.
Q: Do green onions die in the winter?
B: Some varieties of plant can survive frost, although they cannot endure sustained periods of below freezing temperatures.
Q: Do green onions tolerate heat?
A: Yes! They do best in warm climates with humidity, but will go to seed eventually.