Plant Onions in Early Garden

Onions have been a food for man as far back as records exist. They were a staple of workers constructing the pyramids of Egypt. Onions are also mentioned in the Bible. Because they have been spread by man since the earliest periods of history, their exact origin is unknown. However, they are believed to be of middle eastern origin. In addition to being eaten as food, onions were believed to have many religious and medicinal properties. There are three basic groups of onions. The common onion group is the most important, and includes all those that produce large, single bulbs.

Green onions, or scallions, are shoots from common onions that are pulled before the bulb is well formed. Onions of this group are able to produce seeds. The other two onion groups are not abundant seed producers and are generally reproduced vegetatively. The aggregate group includes those that produce a cluster of bulbs at the base. Examples are the multiplier onion and shallots. The proliferous group is a less common type which produces small bulbs in the flower cluster which drop to the soil and take root. The best known of this type is often called Egyptian onion.

Common onions may be grown from sets, transplants or seeds. In all cases planting should be done as soon as the garden can be tilled in spring. Onions start their bulb formation when the daylight and temperatures are proper. Varieties vary in their exact requirements. Since bulb formation is controlled by environment, late planting results in smaller bulb development. Onion sets offer the easiest way to get onions started. These small bulbs develop quickly into green onion which may be pulled for use while thinning the planting to allow development of remaining bulbs for winter storage.

To produce only green onions, set bulbs about one inch apart. For dry onions bulbs should be planted at least two inches apart. Select onion sets that are predominantly made up of small bulbs, since those 5/8 or more inches in diameter normally produce flower stalks and therefore do not store well. If larger onions are included in set of bulbs, these should be planted together so they are easily identified for use early as green onions.

Onion transplants are more frequently used for growing the large, sweet onions such as Yellow Sweet Spanish and the Bermuda types. These small seedling plants, may develop large bulbs and should be planted 4 to 5 inches part, with 12 to 18 inches between the rows. These "sweet" onions do not generally store as well as the more pungent onions grown from sets. Onions are less commonly grown from seeds in our climate, since a longer time is required for development and, therefore, bulb size is normally smaller.

Seeds started very early in coldframes can be used to produce transplants and permits greater selection of varieties not normally available in stores. If onion seeds are planted directly into the garden, they should be thinned to at least 2 inches between plants when they are 3 to 4 inches tall. If long white stems are wanted on green onions, pile up an inch or more of soil around the young plants. Onions grown for large bulbs and storage should not have any soil over them. Good weed control in onions is important, since they have shallow roots and do not compete well with other plants. Shallow cultivation is also necessary to prevent root damaged.

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