Onions are edible bulbs. They are members of the alluim family, along with chives, garlic, leeks and shallots. Onion bulbs are round or oblong and are composed of concentric layers. They can have either a pungent smell or be quite sweet depending on the variety.
Early in the season, onions send up tubular, hollow leaves, before beginning to form bulbs. Both the size and shape of onions varies by type and growing season. The bulb size is related to the size and number of the leaves. Each leaf translates to a ring of onion. Larger leaves make larger rings, so the more leaves, the more bulb.
Onions need at least 6 hours of sun to develop properly.
Harvest onions at any stage. The plants you thin from a row can be used as green onions. However, onion bulbs are ready when about ½ the tops have fallen over and the bulbs’ skins have a papery feel. Bulbs allowed to remain in the ground until 50% or more of the green tops have fallen over will store longer.
Once you see ½ the tops are down, very gently coax the remaining leaves down, without breaking them off the bulb. Then allow the bulbs to sit in the ground and cure for a couple of days before lifting them. Bulbs are best dug rather than pulling. You don’t have to go deep, just enough to loosen the remaining roots. Shake and brush off any loose soil and let the bulbs finish curing in a warm, dry place with good air circulation. Leave the leaves on. You can use fresh onions at any time now.
For storing onions, wait until the outside onion skins dry and the neck – where the leaves meet the bulbs, starts to shrivel. Then store in a cool, dry location, like your basement. Onions keep longer in cool temperatures (35 – 40 degrees F.) but should not be allowed to freeze. Store onions in mesh type bags or by braiding the tops together and hanging. Just make sure they are not piled on top of each other and unable to breath.
If you are buying transplants or sets, you will find types suitable for local garden here at Watters Garden Center in early spring and again during the Autumn planting season.
Granex or Vidalia are large, globe-shaped, sweet onions, and early producer. They come in both red and white varieties.
Texas Grano 1015Y – An improved strain of ‘Yellow Grano’ with treat disease resistance and good storing ability.
Cipollini – Flat, doughnut shaped onions. Store up to 5 months.
Italian Red Torpedo – Red to purple elongated in shape.
Redwing – Red color holds up well. Nice solid bulb. Late season onion, so best from transplants.
White or Yellow Sweet Spanish and other Spanish types – Long season varieties (120-130 days from transplant). Includes ‘Walla Walla’ and the earlier Olympic.