Pelleted Onions - Key Growing Information
Culture: Onions need full sun and fertile, well-drained soil with a pH of 6.0–7.0. Sandy loam is ideal; on heavier soil, use raised beds or raised rows to improve drainage.
Day Length: Day length tells onions when to form bulbs, and the longest summer days get longer the farther north you go. So short-day onions are grown in the South at lower latitudes, while intermediate- and long-day onions are grown farther north. See the adaptation range under each onion type for details.
Days to Maturity: Counted from direct sowing; take off 10–15 days for transplants.
Transplanting: Long- and intermediate-day onions: start indoors 6–8 weeks before the last frost, sowing 1 seed per cell in 128-cell trays or 3 per cell in 1½" plug trays, covered with ¼" of soil. Plant out 4–6" apart in rows 12–18" apart, trimming floppy tops to 5" at transplanting if needed. Short-day onions: start indoors from mid-September to mid-October, 6–8 weeks before you plan to plant out, sowing as above. Or sow straight into a nursery bed, ¼" apart in rows 6" apart, then lift the seedlings gently at 4–6 weeks and move them to their final spot. If nights will drop below 50°F (10°C), cover transplants with medium-weight row cover to protect them from cold and warm the soil, and take it off once nights stay above 50°F (10°C).
Direct Seeding: Where long- and intermediate-day onions grow, sow in April or early May, or as early in spring as the soil can be prepared; in short-day areas, sow in mid-September. Plant ¼–½" deep in a 2"-wide band at about 2 seeds per inch, with rows 12–18" apart. Thin to 1½–2" for the highest yields in rich soil, or to 3–4" for bigger bulbs.
Overwintering: Pick varieties suited to overwintering and sow from mid-August to early September, either directly or in flats for transplanting. Where winters regularly go below freezing, protect plants with row cover; in colder northern areas, grow them in low or high tunnels with row cover inside.
Avg. Direct Seeding Rate: At 20 seeds per foot in 18" rows: 1 oz. sows about 25', 1,000 seeds about 50', 5,000 about 250', 25,000 about 1,250', and roughly 580,000 seeds per acre.
Crop Maintenance: Keep onions weed-free with shallow cultivation. Their roots are shallow, so they need at least 1" of rain or irrigation a week, especially while bulbing.
Disease: Good airflow and crop rotation help lower the risk of leaf disease.
Harvest: Once the necks soften and half the tops are falling over, pull the onions and cure them in an airy spot out of direct sun, which prevents greening, or let them sun-cure in the field for 2–7 dry days before finishing indoors. In very hot or wet weather, cure indoors. Curing takes about 2 weeks, until the tops are completely dry. Short-day onions can also be pulled young as spring or bunching onions, with green tops and small bulbs, and sold in bunches for their mild flavor and edible greens.
Storage: Once dry, trim tops and roots and store in mesh onion bags or shallow boxes just above freezing at 65–70% humidity.
Transplants: On average, 1 oz. yields about 4,900 transplants and 1 lb. about 78,750.
Sized Seeds: Standard on all varieties.
Seeds/Lb.: From 96,900 to 127,700, averaging 112,000.
Packet: 250 seeds per packet, enough for about 12' or 140 transplants.
