April · USDA Zone 5
springWhat to plant in April in USDA zone 5
Spring planting guide for zone 5 (Iowa, southern Wisconsin, northern Illinois, parts of New York) — a 150-day growing season with last frost around late April / early May and first frost around late September / early October.
Sow indoors in April — zone 5
Start these seeds under lights or in a heated propagator so transplants are ready when the outdoor planting window opens.
Sow outdoors in April — zone 5
Direct-sow these seeds into prepared garden beds or large containers. Soil temperature matters more than the calendar date — wait for a sustained warm-up before sowing tender crops.
Transplant in April — zone 5
Move hardened-off seedlings into the garden. Tender crops want soil above 16 °C and night temperatures consistently above 10 °C; cool-season transplants tolerate light frost.
- Brassicas, onions, leeks, potatoes
Prep and planning — zone 5
- Harden off tomato and pepper transplants
Universal April tasks
These apply across most US and UK gardens in April, regardless of zone.
- Harden off transplants before moving them outdoors — 7-10 days.
- Direct-sow carrots, beets, lettuce, peas, and brassicas.
- Start cucumbers, squash, melons, and basil indoors (zones 3-5).
- Plant asparagus, rhubarb, strawberries, and bare-root fruit trees.
- Set up trellises, tomato cages, and row cover hoops.
- Mulch perennial beds once soil has warmed to 10 °C.
Why this works for zone 5
Zone 5 has average annual minimum temperatures of -20 to -10°F (-29 to -23°C) and a frost-free window from late April / early May to late September / early October — about 150 growing days. Classic Midwest growing zone. Most US gardening books default to zone 5 timing. Mulch garlic and perennials before deep winter freezes.
Dates are zone-wide averages. Local microclimates (south-facing slopes, urban heat, lakeside warmth, elevation) can shift the window by 1-2 weeks within the same zone.
UK gardeners — April
April is the UK's main sowing month. Direct-sow carrots, beetroot, lettuce, peas, salad leaves, radishes, spring onions. Plant maincrop potatoes. Sow runner and French beans indoors. Last frost passes in much of the south by month's end — H5 gardens can risk tender transplants under fleece.
Source and methodology
Frost-date averages from NOAA Climate Data Online within USDA zone 5. Hardiness boundaries from the USDA Plant Hardiness Zone Map (2023). Crop timing curated against US Cooperative Extension Service publications (UNL, UMN, NC State, Texas A&M, UF/IFAS, Oregon State) and cross-referenced against the RHS sowing calendar. Curated by the Growli editorial team.
Keep going
- ← March in zone 5
- May in zone 5 →
- All zones — what to plant in April
- USDA Zone 5 — frost dates and crop list
- Full 12-month planting calendar