Hybrid ornamental allium with massive 25 cm spherical heads of small star-shaped violet flowers held on tall stems above strap-like grey-green leaves. The most dramatic of the ornamental alliums.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 4–9 | −34.4 °C to −1.1 °C | Plant tolerates down to this zone |
| RHS hardiness rating | H6 | −20 °C to −15 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 4–8 | −29 °C to −1 °C | Plant tolerates down to this zone |
| Australian (ANBG) zone | Zone 1–6 | −15 °C to 15 °C | Plant tolerates down to this zone |
Growing notes
- Plant in mid-to-back borders — flowers May–June, by which time the strap leaves have yellowed, so site with later-emerging perennials in front to mask the foliage
- Outstanding bee forage — flower heads buzz audibly with bumblebees at peak bloom
- Distinct from the edible Allium species already in the database (chives, garlic, onions, leeks) — Globemaster is a sterile ornamental hybrid grown for the flower head
- Dried flower heads persist through winter as garden structure
Pet caution: Globemaster ornamental allium is listed as potentially harmful to cats and/or dogs. Keep pets from grazing on it, and contact a vet if you suspect your animal has eaten some.
Categories
Related plants
Cross-check Globemaster ornamental allium against your zones