Growing guide · Perennials

Allium

How to grow Ornamental Onion 'Millenium'.

Purple pom-poms deer and rabbits skip.

Light
Full sun
Water
Low
Zones
4–9
Size
15–20 in. tall, 10–15 in. wide
Spacing
12–15 in. apart.
Pets
Not on the ASPCA pet-safe list; keep it out of reach
See sizes · from $34.99
Clump of glossy grassy leaves with round rose-purple allium flower heads

Light

Full sun.

Water

Water to establish; drought tolerant after.

Planting and soil

Plant in spring or fall, crown at soil level, in well-drained soil.

Feeding

None needed.

Pruning

Deadhead before seeds ripen if you do not want seedlings; it can self-sow a little. Cut back foliage after frost.

Through the year

Leaves up in spring. Blooms July into August. Seed heads hold into fall.

If something's off

Rots in waterlogged soil. All alliums are toxic to dogs and cats.

Plays well with

Plant it with friends.

Switch Grass 'Cheyenne Sky'
Panicum virgatumSwitch Grass 'Cheyenne Sky' from $61.99
Stonecrop 'John Creech'
Sedum spurium (Phedimus spurius)Stonecrop 'John Creech' from $29.99
Betony 'Hummelo'
Stachys officinalisBetony 'Hummelo' from $30.99

Why we stock it: Clean foliage all season and a long run of pollinator-friendly bloom when most spring alliums are long gone.

That's everything we know about growing it. Thanks for reading.

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Kits with Ornamental Onion 'Millenium'.

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