What to plant in August — zone 3b
Zone 3b averages its last spring frost around May 25 and its first fall frost around September 15. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.
Direct sow for fall
- Cilantroaround Aug 1
Counts back 45 days from your first frost. Takes a light frost with cover.
- Radisharound Aug 13
Succession sowing 2 of 3 — sow every 14 days for a steady cut.
- Spinacharound Aug 17
Counts back 40 days from your first frost. Frost-hardy — light freezes sweeten it.
- Radisharound Aug 27
Counts back 30 days from your first frost. Frost-hardy — light freezes sweeten it.
Transplant for fall
- Kalearound Aug 2
Last safe transplant date to mature (55 days) before frost on 09-15.
Sow cover crop
- Cover crop (cereal rye + crimson clover)around Aug 16
Sown a month before frost it germinates, holds your soil all winter, and feeds it in spring.
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