Tips on growing onions in your winter vegetable garden
Nothing evokes home cooking more than the aroma of brown onions being sautéed in olive oil with a bit of salt. It’s a smell that warms up the house and announces that dinner is on its way.
Out in the winter vegetable garden the onion family, or alliums as they’re called botanically, includes staples like brown onions, red onions, white onions, shallots, chives, leeks, spring onions and garlic. They’re a great crop to be growing over the winter months, not only because they’re very easy to grow but because they’re essentials for wholesome cooking.
As The Hungry Gardener, we know I love my food…
Whether you’re talking about brown onions, leeks or garlic, all members of the onion family are bulbs. In the case of onions, the bulb is the part we eat. When it comes to chives, it’s the hollow stem and flower that we use in the kitchen. And for leeks, it’s the leaf sheaths that we want to slice up and cook in soups and pies, particularly at this time of the year.
There are a few ways to grow the different types of allium plants. Onions, for instance, are best grown from seed, though for ease, seedlings are available from nurseries. These plants do well in fertile, well-drained soil in full sun. Ideally, you’ll plant seeds in autumn to early winter. Expect to harvest your crop by late spring to late summer, depending on the variety. Onions will indicate they’re ready to collect when the green tops fall over, so resist pulling up the bulbs until then.
Golden shallots, on the other hand, are best grown from bulbs. I recommend planting each one so the top is just covered with soil. Beneath the soil surface, the bulbs will multiply to create a cluster of bulbs which you can harvest down the track. In the kitchen, I often use shallots in place of onions in recipes, or I finely slice and caramelise them in a skillet pan to use like a topping on rice dishes and in soups, with a good piece of buttered sourdough toast on the side.
For those who are new to gardening or are working with limited space, I recommend growing chives. They’ll do well in small gardens, in containers and also inside on sunny windowsills. Start from seed and, as for onions, make sure the soil is fertile, well-drained and exposed to full sun. Once the seedlings are established, you can place mulch around them to prevent weeds competing with your crop. When it’s time to harvest, always chop what you need using scissors, right down at the base of the stem.
The beauty of all these edible allium plants is that they’re versatile and store well. I always think of the classic image of bags of garlic and onions hanging in an Italian-style garage, or a dried string of garlic located conveniently in the kitchen. This is why I dedicate time to my vegetable garden, so I have beautiful produce on hand for cooking and, when there’s excess, to share with friends and neighbours.
Here are some specific tips for growing plants in the onion family:
1. For onions, plan ahead
Bulbing usually takes place after 3-4 months, so plan ahead when you’re planting your crops.
2. Daylight hours
Onion varieties fall into three categories according to the number of daylight hours required to grow them. There are ‘long day’, ‘intermediate day’ and ‘short day’ onions. Generally, I recommend choosing intermediate day kinds – they tend to be the most adaptable, needing 12 or so hours of daylight to bulb.
3. Avoid stress!
Stressful events, such as hot temperatures, drought or being planted at the wrong time, can cause onions to bolt – that is, to flower at the expense of producing an edible bulb. That’s why it’s a good time to plant in winter when temperatures are cooler and rainfall is more reliable.
4. They make great companion plants
Planting garlic among roses and fruit trees helps to repel pests such as aphids. But don’t plant them alongside your corn or bean crops as they will restrict each other’s growth.
5. Use your leftovers
When I buy a bunch of spring onions, there always seems to be one or two left over. Rather than throwing them out, you can plant them straight in the ground and they’ll keep growing. This is a great way to prevent food waste and it’s also cheaper than buying seedlings.