← Learn

Seasonal Planting Calendar

Updated May 2026 · 0 plants · 0 actions

Zone 2bNorthern TierZone 3bNorthern TierZone 4bMountain WestZone 5bMidwestZone 6aMidwestZone 7aMid-AtlanticZone 7bUpper SouthZone 8aSoutheastZone 8bPacific NorthwestZone 9aCalifornia MediterraneanZone 9bGulf Coast / SouthwestZone 10aSubtropical

California Mediterranean stretches 255 frost-free days — long enough for succession plantings, overwintered brassicas, and a real summer heat window. September is the editorial lens for the workhorse month of september gardening. Pick a USDA zone above to compare calendars.

Zone 9a in September

☀️ In-season10 weeks to first frost
September is in-season for California Mediterranean — your 255-day growing season is the long-form gardening calendar. Direct-seed succession crops, transplant the second wave of brassicas, and stay ahead of weeds and water before the first frost window 10 weeks out.

About Zone 9a

USDA Zone 9a (California Mediterranean) has an average last frost of Mar 15 and first frost of Nov 25, giving roughly 255 frost-free days. California Mediterranean — long season, dry summers. Irrigate deeply. Sources: UC ANR Extension, Sunset Western Garden Book & generations of CA gardeners.

Get Zone-Specific Alerts →