Grow Your Own Onions
by Rob Sproule
Onions are one of the world’s most ancient vegetables. Bronze age archaeological sites in Asia have revealed traces of onion cultivation alongside figs and dates. The Egyptians cultivated it as food and to place near the eyes in mummification.
Growing your own onions will allow you to enjoy a much wider variety than is available on the supermarket shelves. They take a long time to yield so starting them early is a must; you can start them from seeds or sets.
From Seed to Seedling
Onion seeds take longer to grow than sets but a wider selection is available. Plant the seeds in clusters of 6-8 and try to germinate them around 15 Celsius.
Germinating onion seeds takes a little patience as they usually take about 3 weeks to emerge. As with all seeds, make sure to keep the medium moist. You’ll want to start in start February in order to give them plenty of time to grow.
As they grow, thin them out several times so the bulbs don’t get crowded and eventually deformed. When you thin them out in the garden, keep the baby onions for the kitchen.
While growing onions from seed is very popular in the south, in our bitter northern climate many people opt to plant sets instead. While they mature faster than onion seeds, if you want to be able to grow unique varieties seeds are still your best option.
Sets are immature bulbs that you can plant directly into the garden as soon as you can work the soil. Plant them about 4″ apart in rows 1 foot across. Snipping the old dead growth off the top I the bulb will make it harder for birds and other critters to grab them out of the ground for a snack.
From Seedling to Eating
Onions are an ideal crop for containers because they bring straight, architectural lines to the aesthetic and take up very little space. Keeping them in containers will also allow you to better monitor them for weeds and pests.
Whether in a container or the garden, plant so that half the onion bulb is above the ground. This not only allows them to soak up the sun, it also helps keep subterranean onion maggots under control.
Onions can’t compete well with aggressive weeds so make sure to keep the area weeded. Adding a layer of mulch will help keep the weeds down, but try to keep the mulch from covering the bulb itself, which needs to be exposed to direct sunlight.
Occasional fertilizing and a watchful eye for weeds will keep your onions thriving. Make sure to keep them moist during periods of dry weather.
If your onion tries to bloom, stop it. Nip the bud off as it forms because, like most vegetables, if it goes to seed it will consider its days work done and will stop investing energy into the yield.
Harvesting and Uses
It’s easier to tell when onions are ripe than many other vegetables. When the foliage turns yellow and keels over, the bulb is almost ready to be pulled.
When harvesting, dig a trowel into the soil around the bulb so that you don’t scrape the onion itself. If you have a spell of dry weather you can dry the onion outdoors by elevating it off the ground but out of the direct sun. If it’s wet and rainy you can cure them inside on an onion rope.
Onions keep for a long time in a cool, well ventilated area as long as they’re dry. Only store undamaged, hard bulbs because they are much less likely to rot.