Zone 10b planting calendar

What to plant in September: zone 10b

Zone 10b averages its last spring frost around January 15 and its first fall frost around December 30. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.

These are zone-average dates. Check an area-level frost estimate from thirty years of nearby weather history and this calendar retimes itself.
Last frost: January 15
First frost: December 30
Winter lows: 35 to 40 °F
Zone 10b Almanac. What growers here actually recorded: sowing weeks, days to first pick, and yields.

Plan & order

  • Inventory and order seedaround Sep 25

    Sort what you already have, toss anything over 3 years old, and order early while varieties are in stock.

  • Order fall seedaround Sep 1

    Fall brassicas and greens get sown in the heat of summer. Have the seed on hand before that window opens.

Start indoors for fall

  • Broccoliaround Sep 4

    Fall broccoli window opens. Sow trays any time in the next four weeks.

  • Kalearound Sep 21

    Fall kale window opens. Sow trays any time in the next four weeks.

Direct sow for fall

  • Parsleyaround Sep 23

    Fall parsley window opens. Sowing now beats the last-minute date by a month of growth.

  • Bush beanaround Sep 28

    Fall bush bean window opens. Sowing now beats the last-minute date by a month of growth.

  • Lettucearound Sep 29

    Succession sowing 3 of 3. Sow every 21 days for a steady cut.

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