We sell Onion Starts at the Garden Center each spring. These are little bareroot plants that were started from seed and harvested after growing for 6-8 weeks. They come to us dormant with dried roots. However, once planted, they plump up and turn bright green. We’ll have the following varieties for the 2017 season:
Red Wing – red onion, stores 8-10 months
Red River Sweet – red onion, super sweet, best eaten fresh during growing season
Walla Walla – white onion, famous, big bulb, sweet, short keeper that stores for 1-2 months
Highlander – white onion, good for long keeping
Lancelot Leeks – big, beautiful leeks great for cooking and soups
Some planting tips:
Onion starts can be planted 4-5 weeks before the last spring freeze. So, that means get them out there with your peas and early greens.
Choose an area that gets full sun all day and prep your site by loosening the soil. Onions prefer to grow in loose, fertile soil that drains well. If it is compact add some compost and fork it in. Onions do well in a raised bed of sorts (or a raised row). A bed or row 4 inches high by 20 inches wide is good. Plant the onions either 2 or 4 inches apart. When planting, fertilize onions with a 10-20-10 fertilizer spreading at half a cup of fertilizer per 10 linear feet. Do not put the fertilizer directly on top of the onions; instead work it in the soil about 4 inches away from the onion. If you planted your onions 2 inches apart, thin them to 4 inches apart after 45 days and eat them as spring onions. This allows the others to mature to a larger size.
Water thoroughly after planting, and as needed thereafter. Onions are shallow-rooted so they will dry out quickly. You never want the soil in your onion patch to be dry and cracked. Every 2-3 weeks fertilize the plants again with ammonium sulfate. Again, half a cup per 10 feet of row. Sprinkle it on top of the other fertilizer. No need to work it into the soil, but do be sure to water well after each application. Stop fertilizing when the onions start to bulb. You’ll know the bulb process is beginning when the soil starts to heave as the onions push it away from their base.
You can harvest your onions any time but if you want big flavorful bulbs wait until you see the green tops start to turn yellow or brown and fall over. This should happen roughly 3.5 months after planting. Now the fun starts. Go out early one sunny morning and pull the onions out of the ground. Leave them on the ground to dry in the sun for 2 days. They are dry enough for storing when the entire neck of the onion is dry all the way to the surface of the onion. You can then clip back the roots and cut the tops, leaving about one inch. They are now ready for eating or storing.
Another fun way to store onions is to cure them and then braid the dried tops instead of cutting them. A braid of onions is a lovely gift for a friend or neighbor! Here’s a video on how to make an onion braid.
It is important to research whether the onions you’re growing are best eaten fresh or if they are good for both fresh eating and storing. Not all onions are good keepers. And nothing smells worse than a bunch of rotten onions.