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Growing Onions

A successful harvest depends on the right bulbs for our hours of light

Onions are good for your health, and generally they are easy to grow. Let me give you some advice on growing them successfully.
    Plant onion sets and you’ll harvest only green onions. Most sets you buy are short-day onions, which produce bulbs only when grown during the winter months with 10 daylight hours or less. Planted in the spring, as daylight hours grow longer, they produce only onion tails, your green onions.
    To grow onion bulbs, you must buy either long-day or intermediate, aka day-neutral, onions. They are shipped in bundles of 75 or more seedlings. Unless you are familiar with a particular variety, I suggest planting two or more varieties. Harvesting will be easier if you keep each separate in the garden, as they’ll mature at different times.
    Onions perform best in high organic soils with a nearly neutral pH.
    The spacing between onion plants is based on the mature bulb size. The most desirable bulb size for kitchen use is one and a half to two and a half inches. For those sizes, use a four-by-four-inch spacing. Bermuda and Walla Walla-size onions need more space; plant them in six-by-six-inch spacing. Those spacings allow room for the bulbs to grow and for you to cultivate between the plants without damaging the bulbs.
    Fertilize two to three weeks after planting and monthly thereafter. Don’t let the soil dry out; onions have a very limited root system, and there is a high population of plants in a limited area.
    Neck rot of onions can be a serious storage problem. Avoid it by knocking the foliage to the ground just as the bulbs begin to mature in late July and August, depending on the variety. Do so as soon as the color of the foliage begins to fade and the tops of the onion tails start turning brown. I use the back of a garden rake.
    Leeks want four-by-four-inch spacing as they do not produce bulbs but do produce thick stems. They have the same growing requirements as onions.
    Garlic planted last fall is now in need of fertilizer. Like onions, garlic plants have a limited root system and respond well to fertilizer and water. Remove the flower buds as they begin to form, mid- to late June, depending on variety. If the garlic plants flower and produce seeds, both bulb and cloves will be smaller. For large cloves of elephant garlic, early removal of the flower stem is doubly important.


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