Allium

Dinner wouldn’t be nearly as delicious without plants from the Allium genus. Ornamental Alliums also attract beneficial insects to your garden. ​​

Freshly harvested onions

Allium species include: 

• chives (A. schoenoprasum)
• garlic (A. sativum)
• leeks (A. ampeloprasum)
• onions (A. cepa)
• shallots (A. ascalonicum)

​Scallions can be the immature stage of many different onion varieties.

​​Alliums are monocots that grow from bulbs. Bulbs are a food reserve for the plant (and your pantry). Similar to grass plants, Alliums feature fleshy layers that wrap around the bulb and stem. Their stems do not have leaves, but a single umbel. Umbels are flowers made up of tiny flowerettes, usually forming a curved or flat surface. This surface creates an attractive landing surface for beneficial insects.

Freshly braided garlic

Attracting beneficial insects

Planting Alliums in the garden is sure to attract beneficial insects. The convenient landing platform and sweet nectar will bring them in from blocks or even miles around. Allium tanguticum, the Lavender globe lily (pictured), attracts hoverflies. These beneficials look like tiny bees and they devour aphids and mealybugs. Spritely black Trichogramma wasps are also attracted. They will lay their eggs in moth eggs, preventing caterpillars, such as the tomato hornworm, from attacking your garden. If you enjoy the flavor of garlic and chives, you can always plant garlic chives (Allium tuberosum), another favorite of beneficial insects.

Lavender globe 'Allium' (pxhere) Public Domain

How to grow Alliums

These shallow-rooted plants prefer soil that holds a lot of organic material and that means adding compost before planting. They will grow just about anywhere, but heavy clay soil can slow their growth. Alliums can be grown in partial shade to full sun. They grow well in raised beds and containers. You can grow chives in a pot on your kitchen windowsill for easy access while cooking!

Growing Alliums from seed can be hit and miss. The plants are slow starters and they don’t handle competition (weeds) very well. You can plant seeds in containers or directly in the garden. Seeds should be sown 1/2” deep and 1/2” apart. Thinned plants can be eaten as scallions.

Another way to plant Alliums is in the form of “sets”. These sets are mature bulbs that can be planted directly in the ground or a container. Follow the package directions for depth and spacing. The only downside to sets is that they tend to bolt. Bolting is the beginning of the going-to-seed process. If you are growing onions, leeks, or garlic, plants that have started bolting should be harvested right away, unless you plan to collect your own seeds.

Garlic and onions are best planted October through January.