CAN I GROW ONIONS AT ALTITUDE WITH A SHORT GROWING SEASON? By Ginger Baer

Onions form bulbs in response to daylength. When the number of daylight hours reaches a certain level, onion plants start forming bulbs. Long-day onions need about 14 to 15 hours of daylight to bulb. Short-day onions need 10 hours of daylight. Day-neutral onions form bulbs regardless of daylight hours and produce well in almost any region. As soon as daylength hits the 10-hour mark, a short-day onion starts forming a bulb. If the top of the plant hasn’t had enough time to grow big and lush, the resulting bulb will be small. Conversely, if you live where daylength never hits 14 hours, long-day onions will never form a bulb. All you’ll get are green leaves or possibly scallions. By choosing the right type of onion for your region, you’ll get healthy green stems that are large enough to fuel forming fat and tasty bulbs. Which onion type you should plant depends on where you live. The general rule of thumb is: ·         In the North (the area north of a line drawn from San Francisco to Wa