Growing brussels sprouts in zone 9b
(Zone 9b = an average winter low of 25°F to 30°F.)
In USDA zone 9b, the typical last spring frost is February 1 and the first fall frost is December 9. Here is when to plant brussels sprouts against those dates.
Typical timing
Zone 9b planting schedule
Evidence trail
How these dates are built
Sprout applies the cited planting offsets to the typical zone 9b frost anchors. The result is a planning baseline for the zone, not a local weather forecast.
- USDA Plant Hardiness Zone Map, 2023USDA Agricultural Research Service / Oregon State University PRISM Group. Supports the USDA hardiness-zone band.
- U.S. Climate Normals 1991-2020NOAA National Centers for Environmental Information. Supports the median spring and fall freeze dates.
- Vegetable Growing Guides: Brussels sproutsCornell University Home Gardening. Supports fall direct-sowing timing (normalized).
Method note
Fall window: 'direct seed about 4 months before expected fall frost', converted to about 17 weeks before first fall frost. Soil pH 6.0 to 7.5, cutworms and cabbage root maggot pests, clubroot. Cornell thins to about 18 inches with rows about 30 inches; the USU spacing is used here.
These are zone 9b averages
Computed from 2,081 ZIP codes in zone 9b. Your town's frost dates vary; enter your ZIP for dates built on your nearest weather station.
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Put these dates to work
The plant profile covers spacing, light, water, soil, and source-backed timing details. The growing guide covers preparation, care, and harvest technique.