Gardeners can keep their homegrown onions fresh for months, but only if they do one important step straight after pulling them from the ground. Onions are among the easiest vegetables to grow, and many people plant them in early spring to enjoy later in the year. By September, spring-planted bulbs are usually ready to harvest, and what you do next can make all the difference.
You’ll know your onions are ready to harvest when the green tops start flopping over at the neck, the part where the stem meets the bulb. This is a natural sign that the plant has stopped growing and is starting to dry out. Most gardeners wait until all the onions in one bed have fallen over before harvesting. At that point, you should pick them within a week to prevent them from being damaged by sun or rain.
The advice comes from Megan, a long-time gardener who shares tips on her blog The Creative Vegetable Gardener.
She grows between 300 and 500 onions each year and stores them for winter.
She said: “My goal is to never buy an onion from the farmers market or grocery store, ever! Most years I succeed and that’s all due to the fact that I’ve learned to grow, cure and store onions for long term eating.”
Megan says the key step after harvesting is curing the onions. This helps them develop the dry, papery outer layer that protects them in storage.
Fresh onions are delicate and can bruise easily. After harvesting, gently brush off excess soil and lay the onions out in a single layer somewhere dry and out of direct sunlight.
A garage, shed or covered porch can work well as long as there’s good air circulation.
“Do not remove the leaves yet,” Megan said. “Leave the onion leaves on during the curing process.
“I prefer to bend my onion over at the neck to seal off the bulb and then lay them out in layers.”
Depending on the weather, onions usually take four to six weeks to cure fully. Once the tops are dry and brown, and the outer skins look like shop-bought onions, they’re ready to store.
Cut off the dried tops and roots, leaving about an inch of neck on each bulb.
Store the onions in crates, baskets or boxes somewhere dark, cool and dry, ideally between 2C and 4C.
Megan said: “In ideal conditions onions can last up to a year in storage. But they’re likely to sprout or sometimes rot before then. Check on your onions weekly.”
Any sprouting onions should be used immediately, and any soft or rotting ones should be removed to stop the damage spreading.
Done properly, this method could keep you stocked with homegrown onions right through to spring.