SWEET ONIONS

The Rev. Dana Prom Smith, S.T.D., Ph.D. (1/06/05)

Sweet onions, as with Caesar’s Gaul, are divided into three parts, not by taste, but by parts of the country. Some are southern and are called short day varieties. They have the longest growing season, the shortest days, and are planted early. Some are northern and are called long day varieties. They have the shortest growing season, the longest days, and are planted later in the spring. The third group of onions is the intermediate day variety which includes most sweet onions except those suited for the deep south.

Flagstaff is smack dab within the boundaries of the intermediate day variety, but laps over into the short day and long day varieties. As with most gardening questions in Flagstaff, onions leave the high country gardener in a quandary. We can try almost any variety of onion except the deep south kind such as the Vidalia, a Georgia peach. The Walla Walla from Washington State works in Flagstaff but may not be as big and lustrous as the ones in the market. With a dollar or more a pop, smaller may be just fine. So what else is new?

The intermediate day sweet onions are all hybrids and descendants of the common onion (Allium cepa.) Our sweet onions descended from seeds of the Bermuda Hybrid onion brought to Texas from the Canary Islands in 1898. The hybrid sweet onions most suitable for the intermediate territory are the Candy Hybrid, the TX 1015-Y Supersweet H., the Cimmaron H., the Italian Red Torpedo H., the Stockton Red H., and the Walla Walla Sweet H. Bermuda onions are seldom grown commercially because of their low yield, but a Bermuda Crystal Wax H. may do well in Flagstaff.

Sweet onions aren’t sweeter than other onions. They have no more sugar content. They are less pungent because their sulphur levels are lower. For instance, the sulphur level of the soil in Vidalia, Georgia, is low. Thus, the fertilzer used in the preparation of onion beds is important.

Sweet onions can be grown from seeds, sets, and plants. Seeds are the least expensive and most unreliable with slow, sporadic growth. Sets are small onion bulbs that have been grown, harvested, and stored over the winter and then marketed in the spring. Sweet onion sets are difficult to obtain. Try haranging your local nursery.

Plants are onion transplants grown in the South in the winter, bundled in bunches of 50 to 100 plants, and shipped to garden centers in the North and West in the spring. They can be obtained from growers directly through the Internet by clicking on "sweet onions" or the name of the hybrid. They are the easiest, most reliable, and most expensive to grow. If ordering plants from the growers, the winter months are the best time to order them.

The soil for all types of onions, as with all soil suitable for vegetables, should be composted or amended with organic matter such as seasoned, vintage manure. Onions require a more fertile soil than most vegetables, and the soil should be prepared with an application of 10-10-10 or 10-20-10 balanced fertilizer. During the growing season a 21-0-0 onion fertilizer should be used. Ample water is important for all stages of growth.

The nice thing about onions is that they can be started as soon as the soil can be worked. Rather than hanging around while waiting for frost’s last icy blast, the high country gardener can plant about a month earlier than the average last frost. Onions are hardy down to 20 degrees which is good news for those who suffer the vagaries of spring temperatures in Flagstaff.

Raised beds are best for onions and just about everything else in Flagstaff. The rows should be about 10 inches apart with the plants 3 inches apart, 1 ½ inches deep. Every other one can be pulled for green onions leaving the remaining onions to mature.

Now is the time to order the plants. Plants can be ordered, to name a few, from Dixondale Farms, P. O. Box 127STK, Carrizon Springs, TX 78834, Piedmont Plant Co, P. O. Box 424, Albany, GA 31702, and Brown’s Omaha Plant Farms, P. O. Box 787. Omaha, TX 75571.

Sweet onions are easy to grow and great to taste.

Copyright © Dana Prom Smith 2006