Growing Onions: The Secrets You Don’t Find In The Books

Onion Harvest
Growing Onions: The Secrets You Don’t Find In The Books

We just harvested our onion crop for the year, and it was our best effort so far. We grew three different kinds, a red, a yellow, and a white. While it feels good to finally have that great harvest, the truth is these onions most likely will not store all through the winter. That is something I did not know when I chose the method of growing that we used. Growing foods that will last the year and into winter, and on into the following spring is part of our mission statement as homesteaders – it’s one of our goals. It isn’t simply enough to grow the food; we also need to be able to store it using as little fossil fuel energy as possible. This is one of the reasons why we place so much value on root-type vegetables: They can be stored in the root cellar, and without using a freezer. Many people in Maine who we speak to about growing food seem to like freezing it. One of our friends has four freezers! It takes a certain amount of electricity to operate that type of infrastructure, so we say “No thanks.” Even though we do ‘can’ some foods, it takes fossil fuels to complete that as well. But onions are one of the foods that we can store, IF we only knew how. Well, we know HOW, but you need to grow the right onions, the correct way. And most books on gardening do not reveal the secrets behind growing with storage in mind.

Let me begin with one of my favorite onions, Cortland, which is a yellow variety. A good tasting onion that should store well. Okay, great. One of my favorite market gardeners explains about how great it is to ‘over-winter’ certain onion types. This is good for being the first farmer at the market with fresh onions, but not so good for homesteaders who wish to store their crop. Why? Because onions are a biennial plant. During the second year, which is what you will have when you over-winter from one year to the next, the plants usually grow a seed scape. So what, you say. If you’ve ever grown onions for a second year and had the scapes, just like garlic, you will notice that they also grow thick necks. Herein lies the rub: A thick-necked onion will not store as well as their normally-necked brethren. So that is lesson number one: Over-wintering is okay, just don’t figure on storing them as long as single-year-grown onions. Our two year onions are about 50 percent thick neck. Not a huge deal. You just need to sort them into the two groups, and use the thick-necked ones first.

So here is our plan going forward. We will indeed over-winter a small amount of seedlings, just not as many, because we can’t eat them fast enough. We start our seedlings in late August, and transplant into the garden in October before the ground freezes. Then we will start new seedlings the following late February, for transplanting into the garden as soon as the ground can be worked, usually April here in Maine, the same time as you plant your peas. For this we will grow some red, some yellow, and a large amount of storage white onions. This group will mature much later than the over-wintered ones.

When we ‘over-winter’ onions, (or parsnips, or carrots, for that matter) we place half-round hoops bent from half inch electrical EMT, over and stuck into the ground every few feet, and cover this arrangement with Agri-Bon. Then when it becomes really cold we add a second covering of poly plastic. This all usually comes off the first of May, though this past mild spring we had taken the covering off in April. I always love looking into these low-tunnels as soon as the snow melts.

Onions Under Low Hoop

Another aspect to growing onions we are putting into play is saving seeds. This will entail letting a few bulbs with a thick-necked seed scape grow to full maturity. This also means that we will not be growing the Cortland variety any longer, as it is a hybrid. In its stead we have chosen a variety known as Ailsa Crag, which has a great history being introduced in 1887 in Scotland. Our yellow for next year is going to be Yellow Of Pharma, which is Italian, and a great storage onion. Our red will be Wethersfield Red, which dates back to the 1700’s, an onion that New England growers had sold shiploads of. Said to be a good keeper. These are open-pollinated, heirloom varieties. I plan to do a blog post about heirloom verses hybrid vegetables in a future installment.

The simplest way to plant onions is to buy what is known as ‘sets’. These are small, the smaller the better, onions, grown to be replanted. Most sets sold in America come from the Netherlands. The problem with this easy way of growing onions is one, you don’t know what variety you are growing, and two, you have a fifty/fifty chance of getting thick seed scapes which cut down on your storage time. The third problem with growing onions from sets is that they are sold by the pound, and you will get all sizes. You want to try to only purchase sets no bigger than a dime because the larger ones have a better chance of going to seed. By the way, merely cutting the scape off does not lengthen the storage durability. We have grown sets in the past, but now we only grow from seed. It just takes a little preplanning.

We also learned that some onions sown and grown the same year can grow seed scape as well. If your weather has an extended dry spell, for example, the plant can become stressed, and might then send up a seed scape. It thinks it is about to die and will want to reproduce.

Most of this information was not in the popular books about gardening. We either uncovered these tips from digging deep into the internet, or by experience. The veteran gardeners out there probably know most of this stuff, but when you’ve only been gardening for four years, this information can take you by surprise.

Stephanie Reiser

About Stephanie Reiser

After many years in retail sales, writing, and part-time editing for a small newspaper in New York, I began studying organic gardening and farming, and animal husbandry. I began to read a lot about homesteading, off-grid living, consumerism, materialism, economics, and economic history.