When to Plant
Allium bulbs should be planted in the fall, typically between late September and November, before the ground begins to freeze. This gives them time to develop strong roots over winter, ensuring a healthy start come spring.
Where to Plant
Select a location that receives full sun — at least six hours of direct light each day. Alliums thrive in well-drained soil and are not suited to areas where water tends to pool. If your soil is heavy or clay-like, improve its texture and drainage by mixing in coarse sand, fine gravel, or compost.
Preparing the Soil
Start by loosening the soil to a depth of 25 to 30 cm. Remove any weeds, rocks, or debris to give the bulbs a clean start. Alliums aren't particularly demanding when it comes to nutrients, but in poor soil, adding some compost can give them a gentle boost.
Planting the Bulbs
Position each bulb with the pointy side facing upward. Plant them two to three times deeper than the bulb’s height — this usually means a depth of 10 to 15 cm. For spacing, leave about 15 to 20 cm between medium-sized varieties, and up to 30 cm for larger ones. For a more natural look, plant them in uneven clusters rather than neat rows.
After Planting
Water the area gently just once to help the soil settle around the bulbs. No further watering is required over winter unless conditions are unusually dry. Alliums are drought-tolerant and prefer to stay dry while dormant.
Spring Growth and Flowering
Shoots will begin emerging in early spring, with flowering typically peaking in late spring to early summer. If your garden soil is especially poor, a light application of low-nitrogen fertilizer in early spring can encourage strong stems and fuller blooms.
After Blooming
Once the flowers fade, you can snip off the seed heads or leave them intact for architectural interest. Most seed heads remain attractive well into summer. Allow the leaves to yellow and die back naturally — this is essential, as it helps the bulb store energy for next year’s growth. Only remove foliage after it has completely withered.
Extra Growing Tips
Alliums make excellent companions to plants like ornamental grasses, catmint, salvia, and late-blooming tulips. They're suitable for beds, borders, containers, and even gravel gardens. If rodents are an issue, consider planting bulbs in baskets or protecting them with mesh. Once established, alliums will return year after year with very little attention, making them a beautiful and dependable addition to any garden.
