Biennial Crop
Requires Full Sun
Requires constant moisture for shallow roots
Plant in the early spring
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Varieties

There are so many varieties of onions. Different types do well in different areas, so be sure to research the specific onion that grows well in your zone. Long Day Onions require 14-16 hours of daylight each day to start forming a bulb and do the best in the northern States Short Day Onions require 10 hours of daylight to start forming a bulb, will grow well in any region. Walla Walla sweet onions (long day) are grown in the Walla Walla region of Washington state, thought to have the unique sweet flavor due to the volcanic matter in the soil. Though it's a favorite, especially in the Pacific Northwest, it actually isn't the sweetest onion in the world. The Vidalia onion (short day) is actually touted the sweetest and can be grown in most zones. Onions are considered biennial because the seeds come in the second year, however we generally treat them as an annual crop to harvest each year. They can be started from seeds, indoors or with small bulbs that have been saved from the previous year, sown directly into the garden beds when the soil is 50F.

Collecting Seeds

An onion will not generally flower in its first year. If you plan to collect seeds from your onions, leave a bulb or two in the ground after harvest. In the spring of the following year they will put up a stalk with a round floral ball. The ball will produce black seeds. When you are ready to harvest, cover the ball with a paper bag, bend over and cut. Shake the seeds into the bag.

Canning/Preserving/Storing

Store your onions a cool, dark and dry place with lots of breathing room. Some people braid the stalks to hang their onions (my personal favorite) some use net or nylon to hang onions in individual hammocks and some use a wood crate, layering onions between straw.

Harvest

I love to pluck a fresh onion out of the garden for dinner, and it's okay to use an onion no matter the size of the bulb. Your onions are officially ready to harvest when the tops bend over. Once pulled out of the dirt, they need to cure. Lay your onions out on a mesh wire for 360 air flow, or hang upside down for two to three weeks.

Soil Type

When preparing your bed for onions, mix in a lot of well rotted organic matter like compost. They prefer pH to be 6.0-7.0. Do not cover with fresh manure, spread well rotted compost along side the rows of onions, but not touching the bulb

Companions

Onions love to grow near anyone in the cabbage family, including broccoli, kale and pok choy. They also like root veggies like carrots, parsnips and beets. Chamomile, Dill and Parsley will all enhance the flavor of onions when they grow nearby. If your roses are having trouble with aphids, plant some onions nearby to deter the pests. Not friendly with: potatoes, beans, peas or asparagus

Common Pests

Onions are generally a natural pesticide not only for themselves, but for other plants in your garden. However, depending on where you are in the country, you could encounter some onion pests including, cutworms, grasshoppers, leafminers, maggots or thrips. Ways to avoid these pests to use only well decomposed organic matter in the soil, don't create swampy beds with too much water, and rotate you onion crop year to year.k

Get your seeds or sets (bulbs) ordered today!
Tomorrow Seeds , Seed Geeks or Nichols Garden Nursery