Onions can be grown on all types of soils although sand or silt loam is preferred. The soil should be well pulverized and have a pH between 5.8 and 6.5. Lower acidity retards growth. Incorporate manure and 5-10-5 fertilizer. Plant as early as possible after danger of severe frost is past. Buy seedling plants or onion sets at the nursery. Seedling plants are good for growing keeping onions and should be spaced 3”-4” apart in the row with 12”-15” between rows. Onion sets should be covered with about 1” of soil. Onions require continuous shallow cultivation to control weeds. When the bulbs reach a mature size and the plant tops break over, they are ready to be pulled. Dry the onions for 3-4 days and then cut off the tops about 1” above the bulb. Dry again for several days before putting them into storage. Store in a cool, well-ventilated, dry place. Onion maggots and thrips are common insect pests and can be controlled by spraying with a systemic insect killer early in the season. Use Maneb or Captan for disease control.
Garlic can be treated in the same way as onion sets. Garlic is usually ready to harvest in about 90 days.
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