How to Grow Allium


Latin Name Pronunciation: al'ee-um

Bulb size: 22-24 cm/12-14 cm/6-8 cm (depending on variety) 

The genus Allium (the Latin means "garlic") includes many garden plants, also known as Ornamental Onion, that grow from bulbs or bulb-like rhizomes. Allium flowers form dense balls of color at the top of strong stems, and they make excellent displays in the garden or in bouquets. Allium flowers range from purple, burgundy, lilac, silvery amethyst, pink, blue, to yellow and white. Some varieties have scented blooms, but their perfume is usually pleasant and not the least bit oniony. The scent of the bulbs and leaves, however, may remind you of onions.

Light/Watering: Most Alliums grow best in full sun, with at least 6–8 hours of direct sun a day. Those we offer require well-drained soil and are longest lived in locations where the soil is on the dry side during summer dormancy.

Planting: Plant Alliums more shallowly than comparably sized bulbs, just 1–2 times the diameter of the bulb deep.

Fertilizer/Soil and pH: Alliums prefer well-drained, fertile soil. Fertilize in fall and spring with any bulb fertilizer.

Continuing Care: The leaf tips of many varieties, especially the tall ones, begin to brown before bloom time. Remove the spent flowers (except from varieties that are sterile, such as 'Globemaster') if you wish to prevent them from self-sowing.

Pests/Diseases: Alliums have few problems except when planted too shallowly or in wet soil.

Companion Plants: Place Alliums behind heavy-foliage plants such as Peonies and Iris. Good for bedding, and in mixed borders. Flower heads are good for drying.

Dividing/Transplanting: Alliums rarely need transplanting or dividing, but this can be done when the bulbs are dormant.

Frequently Asked Questions

How tall do Alliums grow?

The ultimate height of your Allium depends on the variety. Some popular varieties like Globemaster grow several feet tall while others, such as Roseum bulbiferum only grow to around one foot tall.

Will Alliums grow in shade?

No. Most varieties of Allium grow best in full sun.

When should Allium bulbs be planted?

Allium bulbs should be planted in fall—once air and soil temperatures have cooled—for early spring bloom. Gardeners in northerly climes should plant Allium bulbs 6–8 weeks before the first anticipated frost.

Do Allium bulbs spread?

Many Allium plants will self-seed and spread if you let them (but not the Glomaster variety which is sterile). Deadhead spent blooms to prevent self-seeding.

Allium Bulbs We Offer:

 Allium 'Pinball Wizard' Allium 'Pinball Wizard'
SKU: F316005
From $28.00
 Allium 'Globemaster' Allium 'Globemaster' SKU: F312003
From $25.00
 Allium caeruleum Allium caeruleum SKU: F303003
From $12.00
 Allium roseum bulbiferum Allium roseum bulbiferum SKU: F329003
From $13.00