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Planting Onion Seedlings

Plant purchased or home-grown onion seedlings about four to six weeks before your last frost date. Onions need fertile, well-drained soil. Raised beds or mounded rows are best. Photos: Ann Whitman Tip seedlings out of the pot. They should have strong roots and sturdy stems. Gently rinse the tangled roots to remove soil and make it easier to separate the plants. Tease the plants apart, taking care not to damage the roots or stems. Don't let the roots dry out. Make shallow trenches about an inch deep and 12-18" apart in well-prepared, fertile soil. Our [a href=""]Hori Hori Knife[/a] works well, especially in raised beds. Place the seedlings in the trench, spacing them about 4-6" apart. If you want to harvest some as scallions, plant them closer. Pull the soil over the tiny bulbs, burying them no more than 1" deep. Water thoroughly after planting. If you purchased bundled onion seedlings, separate the individual plants. Plant the onion seedlings 4-6" apart in a 1"-deep trench. Cover with soil, burying the bulbs no more than 1" deep. Thin the onions in early summer so that the remaining bulbs are several inches apart. Remove all weeds and keep onions well-watered. Use the freshly harvested thinnings — or scallions — in summer salads or grill them. Onions have shallow roots and need consistent soil moisture. Keep them weeded for the biggest bulbs and harvest. When about 25 percent of the onion tops turn yellow and flop over, they're ready to harvest. Loosen the bulbs with a garden fork and lay or hang them to dry in a well-ventilated place until the tops and roots are dry. Cut off the dried tops, leaving about 1.5-2" of neck on the bulb. Trim the wiry roots close to the bulb and knock off any loose soil. Do not wash or remove the papery layers. Store the trimmed, dried onion bulbs in a dark, cool, ventilated place. Temperatures just above freezing are best. Sort the onions every few weeks and cull soft and sprouting bulbs.