Fall is the time to plant yellow potato onions. Also known as perennial onions, yellow potato onions are edible, like onions, but perennial as in once you have them, you will always have them. I first heard of potato onions (Allium cepa var. aggregatum) from Pam Dawling, manager of the Twin Oaks Community farm in Louisa, VA. She, along with folks who live there, grow a variety of vegetables on 3 ½ acres to feed the 100 people who live in the community. Just reading her blog gives me a lot of great ideas and information on growing vegetables here in Virginia, although on a much smaller scale. I looked to her neighbor Southern Exposure Seed Exchange (SESE) in Mineral for a source of potato onions. SESE sells vegetables, flowers, and herbs that do well in the mid-Atlantic and Southeast (i.e., our hot and humid summers) which makes them a good source of seeds and plants for my area. They too have a blog, a website, and a print catalog full of information for growing veggies in Virginia.
Although I ordered the potato onions in the spring when I ordered seeds, I knew they would not be shipped until the fall. My shipment arrived right before Labor Day and the bulbs were wrapped in a white plastic netting, along with a 4-page pamphlet on cultural requirements.
According to SESE’s pamphlet, potato onions should be planted in early to mid-November for my Northern Virginia area. Because they are bulbs, it is best to plant them in a well-drained, sandy loam soil with a neutral pH. They are heavy feeders; nitrogen should be applied when leaves are 4-6 inches tall but not during bulb formation. The bulbs should be planted with ½ to 1 inch of soil above the bulbs and a 2-3 inch layer of mulch to control weeds and protect against temperature extremes. Rows should be 6 inches apart. I have not decided where to plant them yet but I know I will have to find a full sun, weed free area that I can water often.
By summer, the bulbs should have grown and divided to produce many more bulbs. Each individual bulb should form a cluster of bulbs at the base, which visible in the shipment I received. After I dig up the bulbs, I have to cure them, and then select the large ones to use in the kitchen, like an onion, and re-plant the smaller ones in the fall (hence perennial). I am looking forward to trying these in the garden and cooking with them next year.