Cosmos in Zone 4b
Cosmos bipinnatus
| Start indoors | Apr 10–Apr 17 |
|---|---|
| Direct sow / transplant outside | May 22–May 29 |
| Estimated bloom | ~70 days after planting |
Spacing: 1 per square foot (square-foot-gardening spacing).
Good companions
- Zucchini — Attracts pollinators and beneficial predatory insects nearby.
Where to buy cosmos seeds
Some links on this page go to retailers we may eventually earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a genuine consensus of positive, independent reviews — see the sources cited on each item.
See it growing
Search YouTube for "growing cosmos" videos → (a live search, not a hand-picked video — results vary and aren't vetted by us)
← Back to the full zone 4b calendar · Full companion planting guide · Full plant profile · Plan your beds in the Garden Designer →