What to plant in May — zone 4b
Zone 4b averages its last spring frost around May 15 and its first fall frost around September 25. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.
Transplant out
- Lettucearound May 1
Goes out 2 weeks before last frost — it takes the cold.
- Onionaround May 1
Goes out 2 weeks before last frost — it takes the cold.
- Strawberryaround May 1
Goes out 2 weeks before last frost — it takes the cold.
- Parsleyaround May 1
Goes out 2 weeks before last frost — it takes the cold.
- Mintaround May 1
Goes out 2 weeks before last frost — it takes the cold.
- Tomatoaround May 29
Safe to set out 2 weeks after last frost. Bury 2/3 of the transplant stem — roots form along the buried stem for a stronger plant.
- Pepperaround May 29
Safe to set out 2 weeks after last frost. Pinch first flowers on transplants so the plant invests in roots before setting fruit.
- Cucumberaround May 29
Safe to set out 2 weeks after last frost. Trellis vertically to double yield in the same footprint and cut mildew.
- Zucchiniaround May 29
Safe to set out 2 weeks after last frost. One plant feeds a family. Pick at 6-8 in for the sweetest fruit.
- Basilaround May 29
Safe to set out 2 weeks after last frost. Pinch tips weekly. Once flowers open, leaves lose flavor — snip them fast.
- Winter squasharound May 29
Safe to set out 2 weeks after last frost. Cure 10 days in a warm dry spot after harvest — the skin toughens and storage doubles.
- Basilaround May 29
Safe to set out 2 weeks after last frost. Pinch flower spikes the moment you see them — leaves stay sweet all season.
- Watermelonaround May 29
Safe to set out 2 weeks after last frost. Ripe = tendril nearest the fruit is brown and the ground spot has turned buttery yellow.
- Cantaloupe / Melonaround May 29
Safe to set out 2 weeks after last frost. Ripe fruit slips off the vine with a gentle tug — the smell alone tells you.
Direct sow
- Potatoaround May 1
Soil is ready -2 weeks before last frost.
- Cilantroaround May 1
Soil is ready -2 weeks before last frost.
- Parsleyaround May 1
Soil is ready -2 weeks before last frost.
- Dillaround May 15
Soil is ready 0 weeks after last frost.
- Bush beanaround May 22
Soil is ready 1 weeks after last frost.
- Cucumberaround May 22
Soil is ready 1 weeks after last frost.
- Zucchiniaround May 29
Soil is ready 2 weeks after last frost.
- Basilaround May 29
Soil is ready 2 weeks after last frost.
- Sweet cornaround May 29
Soil is ready 2 weeks after last frost.
- Winter squasharound May 29
Soil is ready 2 weeks after last frost.
- Basilaround May 29
Soil is ready 2 weeks after last frost.
- Watermelonaround May 29
Soil is ready 2 weeks after last frost.
- Cantaloupe / Melonaround May 29
Soil is ready 2 weeks after last frost.
- Bush beanaround May 29
Warm soil — first summer sowing of bush bean.
- Cucumberaround May 29
Warm soil — first summer sowing of cucumber.
- Zucchiniaround May 29
Warm soil — first summer sowing of zucchini.
- Sweet cornaround May 29
Warm soil — first summer sowing of sweet corn.
- Basilaround May 29
Warm soil — first summer sowing of basil.
Plan & order
- Order fall seedaround May 28
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 May 31
Fall broccoli window opens — sow trays any time in the next four weeks.
Turn this into your own calendar
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