Onions and Garlic Can be Grown in Flower Beds

December 18, 2004

By Lee Oliphant, Master Gardener

For years, I resisted planting onions (Allium cepa) and garlic (A. sativum) in my garden beds. Why? Because they inevitably become ripe for harvest in June and July, the time I need beds for maturing summer crops and flowers. Gardeners with limited space are often reluctant to set aside beds for 6 - 8 months for a bulb crop, even though homegrown onions and garlic are particularly delectable; tender, sweet, and mild.

There is a solution for all Allium lovers who want summer flowers and also yearn for homegrown bulbs to enhance gourmet dishes. I plant onions in meandering swales between perennials. This year, with tall cannas at the rear of the bed and ivy geraniums in front, I prepared a two-foot wide, twelve-foot long planting bed for Alliums. Onions and garlic require well-prepared soil. Amend with compost (this is especially important if the soil is clay or very sandy).

Let your taste buds determine the onion variety you wish to grow. Onions are often described according to taste (strong or mild). They come in three distinct colors: yellow, white, and red. Some onions are more pungent or hotter than others; some are harder or softer. Often the softer varieties are milder than harder varieties and are best when eaten raw. The stronger flavored varieties are better for cooking. More important for gardeners than physical characteristics of onions is the specific need for daylight hours in order to set bulbs. Fortunately, we live in an area of California that grows both long-day and short-day onions.

Onions can be grown from seeds, sets, or transplants. Starting onions from seeds gives you the widest varietal choice and is the least expensive. Seeds can be sown directly in the garden before October or after January 1. Sow onion seeds 1/4 to 1/2 inch deep and two inches apart. Thin to 3-4 inches as onions mature. Sets are small, immature onions that can be purchased from nurseries. Plant them, pointy end up, just below the soil surface leaving 3 to 4 inches between sets. In colder areas, plant sets in January or February to give plants time to mature before summer. In cooler coastal areas, late fall or early spring are good times to begin a crop of Alliums.

Garlic is planted and cared for in a manner similar to onions. A few feet of planting will provide an ample supply for most families. Plant bulbs between mid October and mid February. Purchase garlic bulbs from a nursery, and plant each clove blunt (root) end down with the top about one inch below the surface.

Onions and garlic planted in the fall will be ready to harvest in early summer. Allow leaves to become brown. Dig up mature plants. Cure the entire plant in a warm, dry place for a few weeks then braid stems and hang or cut them from the bulb.

These easy to grow bulbs fit nicely into any garden bed. Once you become confident that you can grow traditional onions and garlic among your flowers you may want to extend your planting to include bunching onions, scallions, shallots, and leeks; all part of the big, happy family of Alliums.

University of California Cooperative Extension Master Gardener Volunteers can provide additional gardening information upon request. Call the San Luis Obispo office at 781-5939 on Mondays and Thursdays from 1 to 5 PM, the Arroyo Grande office at 473-7190 on Wednesdays from 9 AM to 1 PM, or the Paso Robles office at 237-3100 on Wednesdays from 9 AM to Noon.  The San Luis Obispo Master Gardener website is at http://groups.ucanr.org/slomg/. Questions can be e-mailed to mgsanluisobispo@ucdavis.edu.