Here's How Deep You Should Be Planting Allium Bulbs In The Garden

Alliums, also known as ornamental onions, are flowering bulbs that will add explosions of color to your garden with their signature pom-pom tops that look like bursting fireworks. They grow in various heights and are available in pink, purple, white, blue, and yellow. In order to enjoy these spring blooms, it's not only essential to know where to plant these bulbs but also how deep they should go in the ground. Because there are around 700 species of allium species in different heights available for planting, the depth depends on the bulb itself. In general, you want to place your bulbs at a depth two to three times the height of your bulb. For example, an allium bulb measuring 4 inches high would need to go at least 8 inches into the ground.

The spacing is also important when planting these bulbs. Again, the bigger the bulb and flower, the more space you want between each grouping. For large alliums like giant allium (Allium giganteum), place three to five bulbs up to 9 inches underground as much as 2 feet apart. Smaller varieties like Allium oreophilum can be planted in clusters of 10 to 15. Place this variety 4 to 5 inches under the ground and space them up to 3 inches apart. While planting these bulbs at the proper depth and spacing them according to size is essential, it's only one part of the equation for growing and taking care of an allium plant. You also need to know where to plant them and how to help them thrive.

To enjoy allium blooms in the spring or early summer, you need to plant them in the fall. Be sure to choose a location that will give the flowers partial or full sun and provide soil that drains well, as allium bulbs are susceptible to bulb rot and other fungal issues. For best results, you want the soil moist but not soggy. It's interesting to note that bulbs aren't the only way to grow these plants. You can collect and save allium flower seeds to grow these plants. That said, it can take years for these seeds to germinate, so if you want timely blooms, bulbs might be the better option. A better propagation method for alliums aside from collecting seeds is to divide the bulbs and plant those in the spring.

When it's time for your allium to emerge, water the area regularly, add some compost to the soil around the seedlings as they start to pop out of the ground, and watch them grow, bud, and bloom. While these flowers are quite impressive in the garden, note that they are also perfect as a cut flower in your home, extending their beauty to all your living spaces. As the season progresses, the blooms fade outside, and the foliage yellows; it's time to remove them from your landscape. Simply pull up the plants by hand. If ready, they will easily separate from the bulb underground. Then, let your allium bulbs rest until it's time for them to produce again next spring.