Ah, scallions, also called bunching onions or green onions. These little bundles of seeming mildness can be used for practically anything you can imagine, from garnishing soup to adding as a base for salsa. They help to balance the flavors of your dish and give it a bit of sharpness. It is easily confused with leeks, another type of onion.
Green onions are quite versatile and easy to grow even if you don’t have much gardening experience. You might be surprised to learn that the process is not as difficult as you might think. All it will take is a little bit of hard work and patience.
Picture a beautifully planted garden with scallions, cress, kale, and tomatoes galore. Now that we’ve settled that image in your head, let’s get you started with cultivating your own food.
Quick Facts About Scallion Plants
- Scientific name: Allium fistulosum
- Type of plant: herb, leafy greens
- Native to: Asia, particularly China
- Light requirement: at least six hours of direct sunlight on most days
- Water requirement: 1 inch of water per week
- Preferred temperature: between 68º to 77ºF
- Size upon maturity: about 6 to 8 inches tall
- Type of native soil: scallions prefer organic, well-draining sandy soil
- Soil pH level: 6.0 – 7.0
- Fertilizer: nitrogen-rich balanced fertilizer
- Word meaning: small onion with long green leaves
- Family: Amaryllidaceae
- Growing season: June through fall.
What exactly are scallions?
With the scientific name, Allium fistulosum, scallions, also known as green onions or spring onions, are a type of onion that is harvested before the bulb has fully formed. They have only a small amount of starch in their outer layers and are usually used raw in salads or cooked in stir-fried dishes.
Scallions are available all year round, but they’re at their best from March until May when the leaves are young and tender. Its leaves are usually discarded because they’re too tough to eat raw (they taste somewhat like garlic). However, they can be chopped up and cooked with other vegetables or added to salads and sandwiches as a garnish.
They are harvested early in their growing cycle, before the bulb forms. The leaves are green and thin, and usually about 10 inches long. Scallions tend to be milder in flavor than bulb onions, and have a sweeter taste with a hint of garlic. They make a good substitute for chives in recipes that call for either of these green alliums.
Cultivation and History
Scallions are a member of the onion family, Allium cepa. They have been cultivated since at least 400 BC in the Mediterranean region, where they were likely used as an herb. They are now widely grown throughout the world, but especially in Southeast Asia and North Africa. The French name for spring onions is “poireau”, which derives from poire, meaning pear, due to their shape. Spring onions were also grown in ancient Greece, where they were eaten raw or cooked.
The Romans also cultivated scallions and used them as an ingredient in many dishes. They even had recipes for pickling spring onions and freezing them for winter use. Scallions are usually available in grocery stores year-round, but they are the least expensive during the winter months when they are in season. They may also be found at local farmers’ markets or grown at home during the spring months.
There are a number of bulbing onion varieties that you can choose from, and each has its own unique flavor and texture. They’re all easy to grow and come in several different colors.
Welsh onions are fairly small, bulb-shaped onions that grow in bunches of 5 to 10 bulbs. They can reach up to 2 inches in diameter and have a mild flavor. Welsh onions are often used in raw dishes such as salads or salsas because they don’t need to be cooked before eating.
The tree onion grows to about 12 inches (30 cm) in height with a similar spread. It has long flower stalks that are covered with small white flowers in early summer. The tree onion has a mild onion flavor and can be eaten raw or cooked. This variety is popular in Asia and Europe and is often used for pickling because it does not produce bulbs. Tree onions are commonly grown as an ornamental plants because of their unique appearance and long flower stalks.
Japanese Bunching Onions
The Japanese bunching onions have leaves that are wider than those of other varieties of scallions so they look like chives but they do not have the same pungent flavor as chives do. This variety can be eaten raw or cooked but should be added at the end of cooking so as not to lose its flavor during cooking time.
Chinese leeks are a popular ingredient in Asian cuisine, particularly Chinese cooking, as well as Japanese cooking. The green leaves and white stems are used as a vegetable that’s similar to scallions or green onions, but with more bite and flavor.
Garlic chives are a variety of chive that has a mild garlic flavor that can be added to dishes for an extra kick. The leaves are also edible, so you can use them as a garnish or add them directly to your food. Garlic chives are usually sold in bunches with multiple stems, making them easy to find at supermarkets and farmers’ markets.
White Lisbon scallions are similar to regular green onions, but they have a milder taste and a slightly longer white stem that is great for use as an individual side dish or garnish. White Lisbon scallions are ideal for growing outdoors because they withstand heat better than other varieties. They also work well indoors if you grow scallions as houseplants.
Red beard green onions have a round bulbs with long green stalks. They are similar to regular scallions but have a sweeter flavor and are often used for garnishes on salads or as an ingredient in Asian cooking.
Serrano green onions have a spicy flavor that is similar to jalapeno peppers. They are usually used raw in Mexican dishes and as garnishes on pizzas and sandwiches.
How to Grow Scallions: A Complete Guide
Allium fistulosum are not as cold hardy as other onions. They need fairly warm conditions to grow well. You can grow them in containers if you live in cooler climates or during spring and fall in warmer climates.
Green onions need at least six hours of full sun each day to grow properly. If your soil is weak or the weather is cloudy, supplement with artificial light or move your herbs indoors during winter months.
Green onions grow in rich soil line that drains well and doesn’t contain too much clay or sand. If you have poor soil, amend heavy with compost to improve drainage and add organic matter like manure or peat moss to increase fertility. Soil pH should be neutral (6-7) for optimal growth.
Preparing The Soil
Soil should be fertile and well-drained. To prepare a bed for growing green onions, loosen the potting soil with a garden fork and remove any stones or debris. Scatter organic fertilizer over the area and use your hands to mix it into the top 4 inches of fine soil line so it will be available to the plants once they start growing.
Water requirements for green onions are minimal, but they should not be allowed to dry out completely or they will go into dormancy due to lack of water. Water deeply once or twice per week during the growing season and avoid overhead watering as much as possible, especially if you have sandy soils that drain quickly.
Scallions need temperatures above 50 degrees Fahrenheit (10 degrees Celsius) to germinate and grow properly. If you live in an area where temperatures fall below 50 F (10 C) during the day, consider to sow seeds indoors under lights or in an unheated greenhouse before moving them in a garden bed outside once nighttime temperatures reach 50 F (10 C).
Pruning is recommended for green onions because it keeps them from flowering prematurely and setting seeds. It also promotes branching, which increases the number of usable bulbs at harvest time. Scallions flower in the spring, so keep an eye out for any buds forming on your herbs during this time. If you see any green shoots developing, simply pinch them off at their base with your fingers or a pair of scissors as soon as they appear. This will prevent them from maturing into seed pods and becoming useless to you as food.
If you notice that some of your scallion plants have already flowered, don’t worry — there’s still time to salvage these plants before they go completely to seed! Simply cut off all the leaves above ground level so that only the white flowers remain visible above ground.
Green onions can benefit from fertilizer after they have been established — usually after their first year in the ground. During the growth season, fertilize your plants every two weeks with fertilizer containing nitrogen (N), phosphorus (P), and potassium (K). For example, use a 10-10-10 fertilizer diluted according to package instructions and water thoroughly after application.
Store them in a plastic bag in your refrigerator’s crisper drawer. Place them at the bottom of the drawer so that they don’t get crushed by other foods sitting on top of them. Green onions have a lot of water content, so keeping them cold will help retain their moisture longer than if you left them at room temperature.
How to Plant Your Scallion Plants
Planting green onion is a simple process and can be done by anyone. Grow green onions in the early spring or late fall if you live in an area where the climate doesn’t get too cold during those seasons.
- Choose a sunny location with rich soil. Prepare a well draining soil bed.
- Work organic matter into your soil at least 6-8 inches deep, removing stones, then level and smooth. This provides nutrients and improves drainage, which reduces the chance of root rot. Mix one part compost into three parts topsoil before planting the scallions seeds or sets.
- Grow scallions in spring or fall in USDA hardiness zones 4 through 9. Direct seed as soon as the soil is workable, 12 inches apart so they have room to grow and develop bulbs without crowding each other. Space rows 24 inches apart so you can reach between them when harvesting your crop later on.
- Thin seedlings once they have emerged by removing some of them from the row so there will be enough room for each plant to grow without crowding others around it.
- Enrich with a gentle flow of water until the ground is saturated and no longer draining freely from beneath your plants. This will encourage your scallion plants to grow roots that help support the leaves as they grow taller than the soil surface.
Tips for Growing Scallions or Green Onion
Growing scallions is easy. They’re hardy, and they grow quickly, but there are a few secrets to growing them even better.
- If you want bigger white bulbs, plant them closer together.
- Harvest the green part of the green onion as needed.
- You can keep a bunch of scallions growing in a glass of water on your sunny windowsill – snip as you need them.
- If you plant too early, they might bolt — that’s what happens when plants go to seed instead of producing more leaves. So wait until after your last frost date before you sow seeds outdoors.
- The seeds are very small, which makes them difficult to handle with bare hands; therefore, it’s better to use a tool like tweezers or toothpicks for planting scallions properly into the ground. Keep them evenly moist.
- If frost threatens at night, cover or bring containers indoors, then take them out again in the morning. You can also try to grow green onions in pots instead. Choose a narrow pot that is at least six inches deep. This will give you more control over where they are planted and you don’t have to worry about them getting too big for your plants! Also, make sure the pot has drainage holes!
- Plant seeds 1/2 inch deep and 1 or 2 inches apart in the prepared soil in rows spaced 6 or 8 inches apart.
- After seedlings emerge, thin to one plant every inch. Thinning them will give you large bulbs.
- If you are growing scallions as perennials, apply a thick layer of mulch in the late fall for cold-weather protection. Remove it in the spring when the soil has warmed. You will get an earlier crop this way.
- For a continual harvest, succession-plant new crops every three to four weeks.
- Check your green onion regularly for signs of bolting, an early flowering stage that results in fibrous roots that are unusable. To prevent seed drop, trim off the flower stalk.
- When green onion flowers, their flavor becomes more intense and you can use it in different ways in your cooking.
How to Harvest Scallion Plants
Harvesting scallions is a simple process. The only important thing to remember is that these onions are root vegetables, and they should always be harvested before the top growth begins to die back. This will ensure that you have a healthy plant for future harvests.
- The best time to harvest scallions is when they’re young and tender (about 8 inches long). If the tops begin to turn yellow or brown before harvesting, cut off the entire immature onion at its base with a knife or garden clippers. This will cause the roots to regrow into new greens.
- After harvesting green onion, wash them thoroughly under running water to remove any dirt or debris clinging to them.
Common Pests, Diseases, and Treatment
There are a few pests and plant diseases that can affect scallions, though most are not harmful to humans if the crop is properly cultivated. The most common pests of green onion include:
These pests are microscopic roundworms, also known as eelworms. These tiny organisms live in the soil and feed on plant scallion roots. They invade the roots of onions and other crops, causing them to grow poorly or not grow at all.
Treatment: Onion nematodes can be controlled by crop rotation with non-host crops such as carrots or sugar beets for two years followed by planting nonhosts for three years before returning to onion growing. It is also important to rotate with nonhost crops when planting garlic or leeks so that they do not become infected.
Downy Mildew is a fungal disease caused by Peronospora destructans. It can affect a wide range of crops, including scallions, but it prefers to grow on members of the Allium family. It causes brown spots or streaks on leaves and stems that can easily be wiped off with a cloth. The spots will gradually spread across leaves until they cover the whole plant. The mildew will also appear on the lower part of the stalk, which may cause it to wilt and die back.
Treatment: The best way to prevent this disease is by avoiding overhead irrigation during hot weather, which promotes excess humidity that encourages the healthy growth of this fungus.
Onion maggots are the larvae of a fly species and are sometimes called onion or bulb flies. They feed on young and mature plants, causing wilting, yellowing, and stunted growth. Severe infestations can kill plants.
Treatment: The damage caused by maggots can be controlled by spraying the base of the scallion plant with an insecticide or cold-pressed neem oil containing pyrethrins or rotenone to kill both larvae and adults before they have a chance to lay their eggs. The best time to spray is in spring when the bulbous base is forming but prior to the emergence of new shoots from the ground; this will prevent further damage from occurring throughout summer and fall when plants are actively growing.
Symptoms include small black spots on scallion leaves that turn brown and become covered with white spores. Leaf blight is caused by a fungus called Alternaria porri and can affect other members of the Allium family as well as members of the amaryllis family (including lilies).
Treatment: Plant scallions in full sun and keep them well watered during dry periods. Remove infected plants and destroy them by burning or placing them in a sealed bag for two to three weeks before disposing of them in the trash. Use fungicides to spray your entire crop if you notice any signs of disease developing on your plants.
Onion thrips can cause leaf damage with their feeding, but this is not usually significant. The real problem occurs when thrips feed on developing bulb scales, which results in greatly reduced bulb size and quality. Thrips also transmit viruses to onion plants, including yellow stripe virus, white stripe virus, and pink vein virus. These viruses can reduce yields by up to 50%.
Treatment: The best way to control onion thrips is to rotate crops annually so they do not grow in the same spot two years in a row. Using floating row covers can help prevent damage from both pests and diseases while allowing good air circulation around plant stems, which helps reduce moisture buildup in beds that can lead to rot problems like black legs.
Best Uses of Green Onions
Scallions are an essential ingredient in many Asian dishes, where they’re used as a garnish or cooked with other foods. They can also be used to replace onion in any recipe.
Scallions make a flavorful addition to salads and sandwiches. You can chop them up and add them raw to your favorite salad recipe, or saute them first before adding them to your meal. Cooked delicious scallions have a milder flavor than raw scallions, so use them sparingly when cooking with raw scallions.
Salsa is one of the most common uses for scallions because it goes well with just about any food imaginable. Salsa is made from tomatoes, peppers, and spices such as cumin or coriander seed, garlic powder, and salt — just about any combination of these ingredients will work well together. You can also make your own salsa by making fresh tomato sauce from scratch instead of buying it from the store.
Homegrown scallions are delicious when cooked with broth, ginger, and garlic. Add them to hot water and let them cook for 10 minutes before adding chicken or vegetable stock, diced tofu, miso paste, and rice noodles.
Scallions can be added to stir-fry dishes to enhance their flavor. Simply chop them up and add them to your favorite stir-fries before adding any other ingredients, such as meat or tofu. The scallions will add a tangy taste to the dish while also adding color and texture.
How many times can you regrow scallions?
You may be able to grow multiple batches from your original batch of scallions before they stop producing new growths at all. However, over time your plants will grow more slowly and eventually stop producing altogether if given too much fertilizer or not enough sun exposure (which is essential for photosynthesis).
Can you get sick from eating too many spring onions?
While there are no known side effects from eating too many scallions, it’s not recommended that you eat more than one or two at a time because they can cause gas and bloating if eaten in large quantities.
Is it safe to eat raw spring onion?
Yes, but you may notice a slight taste difference. Try cooking the onions first and then adding them to your dish. This will reduce the pungent flavor and make them more palatable for some people.
How do you cut spring onions?
Spring onion can be cut into thin slices by using a knife or chopped into small pieces with a pair of scissors. The size depends on the usage for which it is required. For example, if you want to make spring onion soup, then chop them into small pieces so that they get cooked faster and give out their flavor in the soup better than if they were chopped into large pieces.
Scallions are one green you can plant pretty much whenever. They sprout up fast, and since they’re hardy, even if you forget about them for too long, they’ll be okay. They also have far less of an overpowering flavor than full-sized onions, so they are perfect for cooking and utilizing in a variety of dishes. For gardeners that want fresh ingredients but don’t necessarily have a lot of space, this is a great plant to grow.