Slender annual with feathery foliage and continuous open daisy flowers in pinks and whites. One of the easiest and most productive bee plants for the cutting garden.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 2–11 | −45.6 °C to 10 °C | Zones where it can be grown as an annual — not a frost-tolerance rating |
| RHS hardiness rating | H3 | −5 °C to 1 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 2–9 | −40 °C and warmer | Zones where it can be grown as an annual — not a frost-tolerance rating |
| Australian (ANBG) zone | Zone 1–7 | −15 °C and warmer | Zones where it can be grown as an annual — not a frost-tolerance rating |
As a tender annual, Cosmos doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.
Growing notes
- Outstanding bee forage and continuous flowering from midsummer to first frost
- Easy from direct-sown seed in warm soil
- Deadhead for continuous flowering, or leave the last flush to set seed for self-sowing
Categories
Related plants
Cross-check Cosmos against your zones