Whether you are new to vegetable gardening or are a seasoned grower, the feeling of satisfaction is the same when you harvest edibles from your garden. Onions and leeks are very easy to grow if you follow basic steps. The information given on timing and varieties, are specific to N. Central Texas and will help ensure success.
I have a fairly small backyard vegetable area, but I always make room for three or four rows of onions and a row or two for leeks. Because I want many varieties of onions in my garden, and there are about 75 slips per bunch, I often share slips with friends and neighbors. My eyes are bigger than my garden!
To begin, you always want to start with a raised, or in-ground garden space that gets full to part sun and has rich, loose soil that if full of organic matter and has been maintained organically (preferably). For your greatest chance of success, onion sets, or slips, should be planted in the month of January. On occasion, weather patterns can permit planting into the month of February, but in general plant in January. This information holds true for leeks, as well.
Youâ€™ll also want to stay away from planting onions that you may get from a grocery store. You will often not know the exact variety or if it has been treated with a chemical that will deter sprouting. This is not the case with leeks since youâ€™ll rarely see leek slips in a grocery store.
The varieties of onions that North Haven Gardens has chosen to carry are in the short-day or intermediate day classification. Onions are classified according to how much daylight they need in order to form a bulb. The short day onions need 10 to 11 hours; intermediate varieties need 12 to 13 hours; and the long day varieties need 14 to 16 hours. The Short day onion varieties will produce large bulbs anywhere in the state plus they are milder than the other types. So, unless you garden in Amarillo, where the long day varieties will do just fine, we recommend that you stick with the short/intermediate day varieties in the Dallas area. Leeks are not daylight sensitive, so you donâ€™t need to worry about choosing the correct variety for your area.
Our selection this year includes:
Short Day Onions:
Texas Supersweet â€“ is a yellow, globe shaped onion that will store well for 2-3 months. It gets up to 6â€ in diameter!
Southern Belle Red- is a tried and true â€œpurpleâ€ onion that you should never be without. The can get up to 4â€ in diameter. Stores for about 2 months.
White Bermuda â€“ what a kitchen staple! Itâ€™s a bit flatter than the previous ones and about 4â€ if left to mature fully. I find these onions to have some â€˜heatâ€™ to them. Stores for 2 months also.
Yellow Granex â€“ Yellow, semi-flat, 4â€ onion that has a slightly shorter shelf life of about a month.
Super Star - is the only white onion to win All-American selection. Itâ€™s 4â€ in size and stores well for a couple of months.
Candy - is a large (6â€) yellow onion that stores for 3 months.
Red Candy Apple â€“ Lovely deep red, flattened-globe shape onion that store well for 3 months.
We try to bring in some specialty varieties so you can impress your friends even further! My husband and I love Italy and love to cook Italian food several times a week. Cippolini onions are an Italian staple. One of my favorite recipes is oven-roasted cippolini onions with a balsamic vinegar glaze! Theyâ€™re even more wonderful when you can tell your friends that you not only prepared them, you grew them! Cippolinis are small, flat onions with a very mild flavor. Some say they are also a bit sweet.
We will offer the Borettana, a yellow variety that only gets about 2â€ in diameter and Red Marble which is red all the way through. Try these little guys out!
The leek variety we will have is Lancelot. Leeks are not daylight sensitive and are widely adaptable to various climate conditions. The leek is a member of the onion family, but is milder than either onions or garlic. Unlike onions or garlic, leeks do not form bulbs or produce cloves but develop an edible 6 to 10 inch long round stem as much as 2 inches in diameter. Check out recipes for Creamed Leeksâ€¦Oh my goodness..you will think you have died and gone to heaven.
Planting - Unable to plant the leeks or onion slips right away? Remove them from the bag and spread them out in a cool, dry area. The roots and tops may begin to dry out but do not be alarmed, the onion is a member of the lily family and as such will live for approximately three weeks off the bulb. The first thing that the onion and leeks will do after planting will be to shoot new roots.
Dig a trench 4â€ deep, place fertilizer, such as NHGâ€™s Bulb Food (6-8-4) or the NHG Herb and Veggie Food (4-6-5) in the trench, and then add 3â€ of soil on top of the fertilizer. Plant the onion sets approximately one inch deep with four inch spacing. If youâ€™re like me, you want to harvest some early as â€œspringâ€ or â€œgreenâ€ onion. If so, plant the slips as close as two inches apart and harvest every other one early, prior to them beginning to bulb. This leaves room for the remaining ones to get full size. As the onion begins to form, the soil around it should be loose, allowing the bulb to expand. Donâ€™t place any additional soil on top, as this will not allow the bulb to form. Remember that the size of the onion bulb is dependent upon the number and size of the green leaves or tops at the time of bulb maturity. For each leaf there will be a ring of onion; the larger the leaf, the larger the ring will be. The onion will first form a top and then, depending on the onion variety and length of daylight, start to form the bulb.
For leeks, the planting is a bit different. You want to ensure that you have as much of the shaft of the leek remains white and tender. The only way to get this is to plant them deeply, about 4â€, so that only a couple of inches of the leaf is visible. Through the growing process, you will want to mound up soil around the shaft so that sunlight does not get to it to create photosynthesis, or turn it green, and therefore gets tough. When the shaft is about 1â€-2â€ in diameter, approximately around the same time as you are harvesting onions, you will want to use a garden fork to carefully harvest.
Fertilization - About 3 weeks after planting, begin fertilizing with a balanced, organic fertilizer such as NHG Herb and Veggie Food (4-6-5). Repeat fertilization every 2-3 weeks. Fertilize the leeks when you fertilize your onions.
Because Texas weather can be crazy and unpredictable, wild swings in temperature may cause your onion to think it has begun its second season and it should now produce a flower. You canâ€™t stop it from happening, but it does cause a bit of a problem with the shelf life of the onion. The flower stalk that has formed inside the onion will begin to rot after it is harvested. Be sure you use these onions first, before they become fuel for your compost pile!
Harvest â€“ When the stalks fall over, generally in the month of May, itâ€™s time to harvest. Pull, or gently dig up the onion and lightly brush off excess soil. Lay them out in the shade, not touching each other, for a week to dry. Clip off the roots, and cut the stalk off to about an inch from the bulb. I like to store them in a net or in a large basket in the kitchen. If you use a net, tie a knot in between each onion. That way they donâ€™t rest on each other and you can clip the bottom onion off when youâ€™re ready to use it!
Share your bounty with your friends, family and neighbors!
Sandi Holmes-Schwedler, NHG Senior Buyer, TCNP
Texas Certified Nursery Professional
Texas Master Naturalist