How To Grow Onions And Leeks

Are you interested in finding out how to grow onions and leeks in your vegetable garden? If so, you're in the right place, as we've got a helpful article for you today on doing just that!

Onions and leeks are part of the allium family of plants, along with garlic and chives.  They grow upward from a bulb and are mostly quite simple to grow. They are also great for fitting into a small space because of their upright growth.

To grow onions and leeks successfully you will need a relatively sunny site that is well drained. If your soil tends more to clay, you can still grow them but you will need to dig some grit into the soil first to help with the drainage.

How To Grow Onions

Freshly harvested golden sweet onions. (Photo credit: Wikipedia)

To grow onions you can either start from seeds or from immature onions that are supplied as small dried bulbs known as "sets." If you start from seeds, germinate them in a seed tray first and pick the strongest looking specimens to plant out.

Do not add manure or other fertilizers that are heavy in nitrogen. Onions do not like very nitrogenous or acid soil. They will rot if too wet, and unless the weather is very dry, they do not require much watering.

It is possible to grow onions all year round if you have good drainage. You can plant once in the spring and again in early fall. There is no advantage in harvesting them when they are small. Leave them until the leaves begin to die off and turn yellow.

To harvest, dig them up with the leaves intact and let them dry for a couple of weeks until the leaves are completely dried. You can then tie them by the leaves or hang them in nets to store. Most onions store well, but those with thick necks should be used first.

Leeks (Allium ampeloprasum var. porrum) (Photo credit: Wikipedia)

How To Grow Leeks

Leeks like a little more fertilizer than onions. Dig the fertilizer or compost well into the bed and allow a couple of weeks before planting. Leeks also require more water than onions.

Most gardeners grow leeks from seed planted directly into the bed in spring. Spread the seed in rows with about a foot between rows. Thin out the seedlings so that you have a row of plants about 6 inches apart. Be careful when weeding at this stage, because leek seedlings look a lot like grass!

Different varieties of leeks require different growing times so you can spread your harvest by mixing the varieties in your garden. You will probably want some if not all of them to be winter harvesting leeks, which can be ready at a time when your garden is not producing many other vegetables.

Both onions and leeks will suffer if they are surrounded by weeds. They do not have a very strong root system and are easily overwhelmed by competition. Therefore, be sure to weed around them frequently.

To grow onions and leeks successfully year after year, be sure to rotate them to different places in the garden. This will help to protect them from the fungal diseases that they can suffer from.

Plants of the allium family are good for repelling pests that do not like the strong smell, so you can often help other vegetable plants if you grow onions and leeks or garlic around them in a companion planting.