Growing Cosmos in Zone 12
When to plant and harvest cosmos in Zone 12— based on your zone's frost dates.
Zone 12 sits just outside cosmos' ideal range (Zones 2–11), but a good harvest is achievable with careful timing and a little season extension.
Cosmos planting calendar for Zone 12
These months are derived from Zone 12's frost dates — last frost around None, first frost around None.
Start indoors
—
Sow outdoors
January
Transplant
—
Harvest
—
Cosmos care at a glance
- Sunlight
- Full sun (6+ hours)
- Water
- Low — drought-tolerant once established
- Spacing
- 12–18 in apart
- Days to maturity
- 50–90 days to first bloom
- Best zones
- 2–11 (warm-season annual)
Growing cosmos in Zone 12: FAQs
Can you grow cosmos in Zone 12?＋
Zone 12 sits just outside cosmos' ideal range (Zones 2–11), but a good harvest is achievable with careful timing and a little season extension.
When should I plant cosmos in Zone 12?＋
In Zone 12, sow outdoors around January. Zone 12's last spring frost is typically None and its first fall frost around None, which sets the planting window.
When to harvest cosmos in Zone 12?＋
Harvest timing depends on your planting date and variety — cosmos typically matures in 50–90 days to first bloom. See the full guide for harvest cues.
Full Cosmos guide →
Complete care, problems, companions, and harvest tips.
Zone 12 overview →
Frost dates, climate, and everything to grow here.
June in Zone 12 →
What to sow, transplant, and harvest this month.