Don’t Miss the Best Time to Plant Allium Bulbs—It’s Quickly Approaching!

Alliums are a type of ornamental onion that produce globe-shaped, pinkish-purple flowers that are a striking addition to any garden. They come in various sizes, but all allium varieties are relatively easy to grow. And because they are part of the onion family, alliums have a strong odor and flavor that deer and other pests find unpleasant.

Follow these planting tips to ensure you’ll have impressive and vibrant allium blooms in the spring.

How to Plant Alliums in the Garden

Autumn is the best time to plant allium bulbs. Depending on your growing zone, the ideal month to plant them is between September to November; you want to plant allium bulbs after the first frost but before the ground freezes.

Getting allium bulbs in the ground earlier ensures they can establish strong root systems before winter sets in. If you plant them too late, they may not be robust and strong enough by spring, when they begin to flower.

Similar to other spring-flowering plants, allium bulbs need a period of cold to develop strong roots and prepare for spring blooming. As a general rule of thumb, you should plant allium bulbs at the same time as other spring-flowering bulbs such as tulips, daffodils, and hyacinths.

Before adding any bulbs, loosen the soil before planting to give each allium bulb enough space to root and grow. After placing the bulbs, fill the planting hole with rich soil and wait for spring.

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Planting Depth

When planting allium bulbs, you want to plant them at a depth of two to three times their diameter—typically around 4 to 8 inches deep.

Dig a hole that’s at least twice as deep as the bulb and plant the allium bulbs with the roots pointing down and the spike pointing up.

Space Between Bulbs

Alliums do not grow with a spreading habit, so they look great when planted in large, closely-planted groups. They also make excellent cut flowers.

Experts recommend planting allium bulbs relatively close together, about 6 to 8 inches apart. The bigger the bulb, the more space that will needed between each bulb.

Watering

Allium bulbs dislike being soaked with water. Too much moisture will cause the bulbs to rot, so avoid soggy soil at all costs.

Water well after planting. They need less water during their winter dormancy, but make sure they don’t dry out completely. Otherwise, patiently wait for spring.

How to Plant Alliums in Containers

It is possible to successfully plant and grow alliums in containers, but you want to make sure the container is large enough and well-draining, as allium bulbs that soak in water too much can rot.

Start by ensuring the container has drainage holes. Next, fill the bottom of the container with soil, leaving enough room for the required planting depth of the allium bulb size; you want to plant them at a depth of two to three times their diameter.

Lay the allium bulbs in the container, making sure they aren’t touching. Cover the bulbs with soil and water them well and deeply. Make sure they don’t dry out or get too water-soaked during the winter.

Once spring comes around and the alliums are in their active growing period, make sure they are well hydrated. You’ll know if they are thirsty for water if they begin to droop.