When to plant peas in Chicago, Illinois

February 27 – March 13

Direct-sow outdoors · typical Chicago year

Climate basis: NOAA station Chicago Northerly Is, IL (USC00111550), 2 mi (3 km) from downtown Chicago (ZCTA 60602 centroid), elevation 583 ft, on the 1991–2020 climate normals. Direct-sow peas from approximately the dates above, anchored to the median last spring 32°F freeze (April 10). One year in ten still freezes after April 25.

Last spring freezeApril 101-in-10 after Apr 25

First fall freezeNovember 51-in-10 before Oct 24

Frost-free season≈ 208 daysmedian at 32°F

Hard freeze, 28°Apr 1 – Nov 15kills even hardy greens

USDA zone6b-5 to 0°F winter low — not frost timing

The Chicago year

Direct-sow outdoorsFeb 27 – Mar 13

indoors under lights
in the garden
frost-free season
1-in-10 years still freeze to Apr 25

Peas in Chicago · freeze context from Chicago Northerly Is, IL, 1991–2020 normals.

Every method, with its sources

Direct-sow outdoors

Feb 27 – Mar 13

Purdue: hardy — plant 4–6 weeks before the last spring frost. Penn State earliest sowing Apr 1 (−30 days) sits inside that range; UNH says as soon as soil thaws. Anchored to the median last spring freeze (Apr 10). Purdue University Extension · Penn State Extension (York County Master Gardeners) · University of New Hampshire Extension

Start seeds indoors

Not calculated

Peas are direct-seeded; transplanting is not part of the cited timing guides.

Transplant outdoors

Not calculated

The cited extension guides do not time an outdoor transplanting window for this crop.

Fall planting

Not calculated

No source-backed fall planting rule exists for this crop in the registry, so no fall window is calculated.

Variety assumption: Assumes an average shelling/snap variety (about 60–70 days; Penn State lists 65).

These windows describe typical years (1991–2020 climate normals), not this year's forecast. Freezes happen outside them — especially in frost pockets, valleys, and urban edges. Watch the forecast before committing tender plants.

This week, not a typical year:

Crop rule sources (3)

Purdue University Extension: Indiana Vegetable Planting Calendar (HO-186-W) (accessed 2026-07-24)
Hardiness classes: hardy = plant 4-6 wk before last spring frost; semi-hardy = 2-4 wk before; tender = after average last frost; very tender = at least 2 wk after. Table 2: fall planting at least 4-8 wk before first fall frost.
Penn State Extension (York County Master Gardeners): Vegetable Seed Planting Guide (accessed 2026-07-24)
Earliest/latest sowing dates for a May 1 last-frost / Oct 1 first-frost baseline; offsets derived by date difference from May 1. Also days-to-maturity figures.
University of New Hampshire Extension: Growing Vegetables: When to Plant Your Vegetable Garden [fact sheet] (accessed 2026-07-24)
Per-crop 'time from seed to transplant' and 'safe to set out in garden' relative to last frost.

Keep exploring

This crop, other cities

Related crops in Chicago

Local overview