What to plant in April — zone 4a
Zone 4a averages its last spring frost around May 20 and its first fall frost around September 20. Everything below is timed from those two dates, so it stays useful whether you're planting for summer or for a fall harvest.
Dormant care
- Pre-sprout seed potatoesaround Apr 8
Chit potatoes in a bright, cool spot for 2 weeks — sprouted pieces jump ahead once planted.
Start indoors
- Tomatoaround Apr 8
6 weeks of indoor growth before your last frost (05-20). Bury 2/3 of the transplant stem — roots form along the buried stem for a stronger plant.
- Kalearound Apr 8
6 weeks of indoor growth before your last frost (05-20). Fall crop sweetens after first frost — plan a July sowing for the best flavor.
- Broccoliaround Apr 8
6 weeks of indoor growth before your last frost (05-20). After cutting the main head, side shoots keep coming for weeks — don't pull the plant.
- Basilaround Apr 8
6 weeks of indoor growth before your last frost (05-20). Pinch tips weekly. Once flowers open, leaves lose flavor — snip them fast.
- Basilaround Apr 8
6 weeks of indoor growth before your last frost (05-20). Pinch flower spikes the moment you see them — leaves stay sweet all season.
- Lettucearound Apr 22
4 weeks of indoor growth before your last frost (05-20). Succession sow every 2 weeks. Harvest outer leaves for a cut-and-come-again supply.
- Cucumberaround Apr 29
3 weeks of indoor growth before your last frost (05-20). Trellis vertically to double yield in the same footprint and cut mildew.
- Zucchiniaround Apr 29
3 weeks of indoor growth before your last frost (05-20). One plant feeds a family. Pick at 6-8 in for the sweetest fruit.
- Winter squasharound Apr 29
3 weeks of indoor growth before your last frost (05-20). Cure 10 days in a warm dry spot after harvest — the skin toughens and storage doubles.
- Watermelonaround Apr 29
3 weeks of indoor growth before your last frost (05-20). Ripe = tendril nearest the fruit is brown and the ground spot has turned buttery yellow.
- Cantaloupe / Melonaround Apr 29
3 weeks of indoor growth before your last frost (05-20). Ripe fruit slips off the vine with a gentle tug — the smell alone tells you.
Transplant out
- Raspberryaround Apr 8
Goes out 6 weeks before last frost — it takes the cold.
- Blueberryaround Apr 8
Goes out 6 weeks before last frost — it takes the cold.
- Applearound Apr 8
Goes out 6 weeks before last frost — it takes the cold.
- Peararound Apr 8
Goes out 6 weeks before last frost — it takes the cold.
- Rhubarbaround Apr 8
Goes out 6 weeks before last frost — it takes the cold.
- Kalearound Apr 29
Goes out 3 weeks before last frost — it takes the cold.
- Broccoliaround Apr 29
Goes out 3 weeks before last frost — it takes the cold.
- Chivesaround Apr 29
Goes out 3 weeks before last frost — it takes the cold.
- Strawberryaround Apr 29
Goes out 3 weeks before last frost — it takes the cold.
Garden care
- Wake the bedsaround Apr 15
Turn in compost, cut down cover crops, and let the soil warm two weeks before the first sowing.
- Harden off early transplantsaround Apr 22
Two weeks of increasing outdoor time keeps cold-hardy seedlings from stalling when they go out.
Direct sow
- Peaaround Apr 15
Soil is ready -5 weeks before last frost.
- Lettucearound Apr 22
Soil is ready -4 weeks before last frost.
- Spinacharound Apr 22
Soil is ready -4 weeks before last frost.
- Radisharound Apr 22
Soil is ready -4 weeks before last frost.
- Carrotaround Apr 29
Soil is ready -3 weeks before last frost.
- Kalearound Apr 29
Soil is ready -3 weeks before last frost.
- Beetaround Apr 29
Soil is ready -3 weeks before last frost.
- Onionaround Apr 29
Soil is ready -3 weeks before last frost.
- Broccoliaround Apr 29
Soil is ready -3 weeks before last frost.
- Chivesaround Apr 29
Soil is ready -3 weeks before last frost.
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