In America, there are wild Alliums known as wild garlic or ramps. The onions we cultivate in our gardens today likely originated from a wild Asian onion, but has been grown so long, the road back to the original is lost. Two thousand years ago, there were many varieties that we would recognize today. There were round onions, white onions, red onions, flat onions, long onions, keeper onions, sweet onions, spicy onions. Onions have been important for their perceived health benefits in times gone past and proven health benefits today as well as the fabulous taste they add to an array of dishes.
Onions are easy to grow, have little to no pest problems and are a perennial to boot! Onions have shallow roots, like to be moist, but can’t stand being waterlogged. You should enrich the soil with plenty of organic matter before planting. As common sense would tell us, they also like loose soil. Organic matter helps this along. Onions can be grown in the ground or in pots. My perennial Egyptian walking onion has been growing in its pot for 8 years.
In the Midwest, seeds can be started indoors in early February and transplanted outdoors in March. Transplanting should be done 4-6 weeks before the last spring freeze for spring planting. Since onions are perennials you can also plant in the fall, October for our Zone 6/7 garden. For multiplier type onions or Egyptian walking onions, fall planting will provide a bigger harvest next spring and summer.The more popular method of starting onions is planting “sets.” Young onions that are put out in early spring as soon as the soil can be worked, just as the daffodils begin to fade.
You can place them close together and pull for scallions until the bulbing onions are 5-6 inches apart. As the bulb reaches full size, you can pull the soil away from the top of the onion to help the bulb and neck cure for harvest.
You can also plant the bottoms of store bought onions. If you get enough of the bottom, the onion will take root and give you an onion next season.
Onions tell you when they are ready to harvest, when half of their tops fall over. What can be easier than that? Like garlic, they should be lifted rather than pulled from the ground and leave them in shade for about a week to harden. I use a trowel to dig under the bulb and pop them out. You don’t want to nick them or they will not store well. If you do, keep them in the fridge and use them first.
So, how do you choose which onions to plant? The best bet is to talk to your local nursery to see which grow the best in your area for the ones that thrive in your climate.
There are 3 types of bulbing onions: short day, intermediate day, and long day onions. Intermediate and long day varieties have been around for a long time. Short day onions are relatively newcomers. Onions are sensitive to daylight hours. They start forming bulbs when daylight hours hit a minimum. For long day onions, it is 15 hours. For intermediate, it is 12-13 hours. Short day onions are 9 to 10 hours.
I would have thought long day onions would be for further south, but this is wrong. The north gets the really long summer days (think of Alaska in June with no darkness). Long day onions should be planted in states north of the Oklahoma/Kansas border (approximately 36 degrees latitude). Long day onions are planted in states in the northern part of the US. Intermediate in the middle and short in the South. Short day onions are planted in the fall and form bulbs in the spring. Intermediate and long day onions are typically planted in the spring as sets, not seeds. Seeds require sprouting indoors and transplanting. So, if you want a sweet onion and live in the Midwest, Vidalias are not the best bet since it is a short day type. A better choice is a Walla Walla or a Sweet Spanish.
The other thing to keep in mind is that, like wine, onions pick up the terroir they are grown in. You can grow the exact same onion as you buy in the store or at a farmers market but have a different taste because of the differences in your soil.
There are many fun onions to grow besides the round ones. There are the flat disk like Borrettana Cipollini or the Red Baron onion that is a red scallion type onion. Of course, there is the onion made famous in French cooking, the shallot-French, Gray or Sante are well known varieties. Then, there are onions for keeping over the winter like Rossa Di Milano, Early Yellow Globe, Sweet Sandwich, and Granex Yellow.
Onions will also keep over another year. When onions I planted last spring did not get to decent size, I left them over the winter. They gave nice bulbs in the summer.
Another type of onion is the Egyptian walking onion. It is a perennial that you can pull year round. They do not form bulbs. They are about the size of a large scallion or leek, getting an inch or two wide and 3” long bulb. They also grow great in a pot. When they get their bulblets, they remind me of Medusa. Really cool. You just snap off the bulblets and plant them for more onions next year. They also multiply underground year after year. They are one of my must haves in the garden since they can be harvested year round. Their bulb is great as a cooking onion and their greens as a chive.
Onions are a great addition to the garden. They are perennials, easy to grow and have little to no pest problems. I really like the perennial type onions, the Egyptian walking onions and multiplier onions like potato onions. The Egyptian you can just leave in place and harvest from year round. The multiplier potato onion has a very long shelf life indoors for a storage onion. When you harvest it, just leave behind the smaller onions and they will multiply again for next year’s harvest.
For more tips on organic gardening in small spaces and containers, see Melodie's blog.
Photos: top, Egyptian walking onion; middle, bulbing onion.