USDA Zone 11 planting calendar
When to plant kohlrabi in USDA zone 11
Sowing, transplant, and harvest dates calibrated to zone 11's 365-day season (Florida Keys, Hawaii (most), Puerto Rico, southern California (coastal)).
Key dates for kohlrabi in zone 11
| Stage | When | Anchor |
|---|---|---|
| Direct sow outdoors | October — February (the cool dry season is your spring) | No frost — plant in the cool months |
| First harvest (estimate) | ~55 days after sowing | ~55 days from sow |
Dates are zone-wide averages. Local microclimates (south-facing slopes, urban heat, lakeside warmth, elevation) can shift the planting window by 1-2 weeks within the same zone.
Why this timing works for zone 11
Zone 11 has average annual minimum temperatures of 40 to 50°F and a 365-day frost-free window from no frost to no frost. Kohlrabi are hardy enough to handle light frost — and in fact prefer cool weather. They bolt or turn bitter once daytime temperatures consistently climb above 24 °C, which is why earlier is better in zone 11.
Kohlrabi is a fast-maturing brassica that tolerates light frost down to about -4 °C but turns woody and pithy when daytime temperatures exceed 27 °C; transplant or direct-sow 3–4 weeks before the last spring frost for a summer harvest, or time a second sowing so plants mature in the cool days of early autumn. Harvest promptly when the swollen stem reaches 5–7 cm (2–3 inches) in diameter — larger bulbs become fibrous. Succession-sow every 3 weeks to extend the harvest window.
Quick-grow guide
- Sun: Full sun — 6+ hours direct.
- Soil temperature for germination: 7-29 °C (45-85 °F).
- Spacing: 6-9 inches (15-23 cm) between plants.
- Days to harvest from direct sow: ~55 days.
- Plant in cool weather and provide afternoon shade once temperatures climb above 24 °C.
Common mistakes — zone 11 × kohlrabi
- Spring planting: zone 11 springs are too short — sow kohlrabi in autumn for a winter and early-spring harvest instead.
- Waiting for "warm" soil — these crops germinate at 7-10 °C and bolt the moment summer heat sets in.
Source and methodology
Frost-date averages from NOAA Climate Data Online within each USDA hardiness zone. Hardiness zone boundaries from the USDA Plant Hardiness Zone Map (2023). Crop timing offsets calibrated against US Cooperative Extension Service publications (UNL, UMN, NC State, Texas A&M, UF/IFAS) and cross-checked against the RHS sowing calendar for en-GB readers. Curated by the Growli editorial team.
Keep going
- How to grow kohlrabi — full guide
- USDA Zone 11 — frost dates and what else to plant
- All 13 USDA hardiness zones