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Tips for Successfully Growing

Onion Sets/Slips

Sunlight : Onions grow best in full sunlight as it is needed for proper growth and development of the onion.

Soil Preparation: Add manure, mushroom compost, and/or sand to area several weeks before planting. The soil should be loose, fertile, and have adequate draining with a pH between 6.0 and 7.0. Keeping the soil loose throughout the growing will eliminate stress caused by compacted soil and increase the bulb size.

Planting: Onions can be planted in wide rows for maximum production. Onions do best when they are planted on a mound about 6 to 8 inches high and 20 inch wide. In the center of the mound make a 4" wide by 4" deep fertilizer strip.The fertilize in the strip will spread through the entire mound when you are watering the row. Plant bulbs shallow, no more than 1” deep and about 2" from the outside of the mound. Planting this way will give you two row of onions per mound. Planting on a mound like this will help to keep the onion from standing in water and also help with the dirt being pushed away from the bulb as it grows. For “green onions” plant about 2-3 inches apart. For full size onions, plant 4-6 inches apart. Some people will plant 2-3 inches apart and as the onion grows they harvest ever other one as a green onion which is called a spring onion and leave the other plants to make a large onion.

Fertilization: After 1 month of growing, side dress with 10-10-10 fertilizer or feed foliage with a mild solution of fish or seaweed emulsion. In the early stage of growth you need to promoted as much top growth as possible which will make for a bigger onion. So it is best to side dress the onion plants with 10-10-10 about ever 3 to 4 weeks. If you are growing on a mound add more fertilizer in the fertilizer strip about ever 3 to 4 weeks.

Growing/Harvest: For “green onions,” harvest every other onion and leave remaining bulbs to grow into full size onions. For larger onions, keep soil pulled away from the upper 2/3 of the bulb. Do not allow plants to flower. Water regularly until tops begin to yellow and then withhold water to allow skins to ripen. This will take a few days. Fold tops over to allow sun to reach bulbs. Once tops are dry, pull onions place in the sun to dry. Store in cool, dark, dry, well ventilated place.