If you’d prefer not to start the green onions from seed, choose red, white or onion “sets” to plant. These look like bare-root mini bulbs that come bound with twine or rubber bands. You can pick up a few sets to use as scallions, and let the others mature into onion bulbs. [1] X Research source
Be sure rocks, sticks and weeds are cleared away before you till and work the soil. You can till the soil using a garden rake if you’re working with a small patch. For a bigger area, buy or rent a soil tiller to make the job easier. If you just want a few green onions, you can prepare a pot with a compost-rich potting soil instead of planting them in the ground.
The onion seeds will germinate when the soil is anywhere between 65 to 86 degrees Fahrenheit (18. 33 to 30 degrees Celsius). It may take up to a month for onion seeds to germinate. If you live in a cold climate with a late spring, you can start the seeds indoors about eight weeks before the last frost. Plant the seeds in peat seed starter pots and keep them well-watered. Put them in a warm, sunny room to during the germination period. When the ground outside is warm enough to work with, transplant the seedlings to the garden or a larger pot.
If you’re growing your green onions in a pot, you can skip this step, since weeds won’t be an issue and you can more easily control the moisture level.
Another way to determine whether the onions need watering is to test the soil conditions. Insert your finger, up to the second knuckle, in the soil close to where the plant is. If you feel that the soil is dry, water it. If you think the soil is wet enough, don’t worry about watering, and repeat the test again in a few days. If your area has received rain recently, you may not need to water.
If you want to let some of the plants mature into storage onions, simply leave them in the ground. The bottom of the plants will begin to form a bulb, which will be ready for harvest in the fall. If you only want to use the green part of the onions, and not the white part close to the roots, you can use a pair of scissors to simply cut off the green tops. Leave an inch or two of growth. The onions will continue to grow, and you can harvest the greens again once they’re 6 to 8 inches long. Note that they will become stronger-tasting as the plant matures.
You can grow green onions indoors any time of year, as long as you maintain the correct conditions. The onions need full sun, so they should be placed in a window that receives light for most of the day. Be sure the temperature never drops below freezing. Keep the soil evenly moist. Water every few days, or when the soil seems to be getting dry. Don’t overwater the onions, though - the soil should be moist, but never soggy.
Any green onions bulbs will work, but you might have the best luck if you use green onions that were grown nearby. That way you know they’ll grow well in your climate. Try starting with green onions you bought at the farmer’s market, since they were probably grown in your region.
If you want to continue growing onions year round, then put some rocks and pebbles in the bottom of the jar. Then, place soil over the rocks and pebbles and plant the bulbs in the soil.
