Daily Archives: January 28, 2009

Onions : All You Need to Know


We bought our onion sets and got them in the ground this past weekend in between rain showers. I did a whole slew of research about onions this past weekend and thought I’d share what I learned:

The Most Important Thing About Onions
The thing to keep in mind when growing onions is how suitable they are for your growing region. Check in with your local nursery. If they are good, they will only carry onions that grow well in your area. Onions like a determined amount of sunlight each day. Long-day varieties which are suited for the northern latitudes need 14-16 hours of sunlight a day. Short-day varieties need 10-12 hours of sunlight. And Intermediate or Day Neutral need about 12-14 hours. These ‘day-neutral’ varieties can be grown just about anywhere. If your onions are given improper amount of sun they will either bolt too quickly or won’t bulb out at all.

Shelf Life of Onions
Another thing to keep in mind when planting in quantity is thinking about the storage life of your onions. Long-day varieties tend to be the longest keepers, Intermediate-day onions have a moderate shelf life, and short-day onions don’t keep well at all.

Seeds, Sets & Transplants
You can grow onions from seed, sets (small bulbs) or transplants. From our experience, seeds are difficult to get started and transplants are the most expensive option. We usually get sets when they arrive at our nursery in January. We bought 60+ (there were actually more than 60 in our bundle) for $3.99. They are easy to plant and hardly any have died on us.

When to Plant Onions
If you live in a mild-winter area like we do, you can plant seeds in fall through early winter and plant sets anytime in winter. If you live in a cold-weather area, you can start seeds indoors in winter and plant them out as soon as the soil is workable.
What Onions Like
Onions like most veggies, like loose, rich, well drained soil. They like to be placed about 4-5 inches apart in a sunny location. As you can see above, we put a sheet of metal fencing over our raised bed and plant a set in each square. It is an easy way to get your onions (and garlic) perfectly planted. Since onions are fairly shallow rooted you don’t need to water too deeply, but make sure they get watered frequently.

Onions also like to be well feed, so if you aren’t planting them in a spot where you’ve planted green manure, you want to make sure you feed them regularly with an organic fertilizer or mulch them with grass. The bigger and stronger the plants, the bigger the bulbs.

Good Companions to Onions
After we had filled two full raised beds full of onions sets, we still had a pile of left over onions to contend with. We looked at our favorite book Carrots Love Tomatoes and found that we could interplant our onions with any member of the cabbage family, beets, strawberries, tomatoes and lettuce. But that they do not like peas and beans at all. Now our strawberries are peppered with onion starts. Scott reminded me that we put some in the strawberry bed last year and those onions did the best of all last year. We’ll see how they do this year.

How to Harvest
You’ll know when it is time to harvest your onions when the tops have yellowed and have started to fall over. At that point, pull out your onions and leave them on the ground to dry for severals days in the sun. Use the tops of the plants to shade the bulbs to prevent sunburn. Once the tops have dried completely, pull them off the onion bulb, brush of the dirt and store them in a dark, cool, well ventilated area. For us this means in a box in our laundry room. This room doesn’t receive heat and we rarely turn on the light so it seems to be a good spot.

What Onions We Chose
We chose two varieties, Super Star Onion and Red Candy Apple Onion. The Super Star onion is an intermediate length grower, which means that it isn’t particularly sensitive to how many hours of sunlight it receives, which in turn makes it easy to grow just about anywhere. It is a mild, sweet, large onion (up to 1lb each) and they claim that it tastes good raw. Although ever since my last pregnancy I can’t seem to stand the taste of any kind of raw onion, so we’ll see about that. It should be mature in about 100 days, so let’s see how we do. That would put us right around May 5th. Cinco de Mayo. I’ll report back. Although it looks like last year we pulled most of our onions around July 4th.

Our red variety choice was the Red Candy Apple onion. This also is an intermediate or day neutral in terms of sunlight it receives. The name Red Candy Apple comes from the fact that it is so sweet you can eat it like an apple.

Have you planted your onions yet? Do you have any growing tips to add? What varieties do you want to plant?


Filed under Onions