When should I plant radishes in ZIP 60601?

In ZIP 60601, the main radishes target is around Mar 28, based on the representative Chicago frost station and USDA zone 6a.

When should I start radishes seeds indoors in 60601?

Radishes is usually direct-sown for ZIP 60601. Use the Mar 28 planting window instead of starting it indoors.

Is this a guaranteed planting date?

No. GrowZone uses frost-date estimates, hardiness zones, and crop timing rules for planning. Local microclimates and current weather can shift the right date.

ZIP 60601 planting calendar

When to plant radishes in Chicago, IL - Zone 6a

Q: When is the first frost in Chicago?

Chicago (ZIP 60601) has an average first fall frost around Oct 20, leaving about 178 frost-free days.

In ZIP 60601, plant radishes around Mar 28; this uses the Chicago frost station, USDA zone 6a, and radishes timing rules.

Your Chicago calendar has a 178-day estimated frost-free season. This estimate uses the representative Chicago frost station, USDA zone 6a, and radishes timing rules.

Source: chicago-ohare frost station, USDA zone 6a, last updated 2026-06-28. Verify locally before planting high-value crops because microclimates, current weather, and yard exposure can move the safe date.

Reviewed by GrowZone Editorial. Calculated from the chicago-ohare frost station and USDA zone 6a, last updated 2026-06-28.

In the Chicago area, radishes timing follows the Chicago frost window, so the local ZIP date can differ from a broad zone-only calendar.

USDA zone 6a Chicago frost station University of Illinois Extension Updated 2026-06-28

Read the method

Answer first

When to start radishes seeds indoors in Chicago

In ZIP 60601, radishes is usually direct-sown around Mar 28 instead of started indoors.

Radishes is normally direct-sown in Chicago. Use around Mar 28 as the outdoor planting window for ZIP 60601.

Seed starting schedule

Radishes dates for Chicago, IL

Step	Date	How to use it
Direct Sow	March 28, 2026	Sow seed outside when the crop and soil can handle the window.

Last frost

When is the last frost in Chicago?

Chicago (ZIP 60601) has an average last spring frost around Apr 25.

First frost

When is the first frost in Chicago?

The average first fall frost is around Oct 20, giving about 178 frost-free days.

Season map

Radishes windows by month

JanFebMarAprMayJunJulAugSepOctNovDec

Direct sow

Mar 28

Harvest

Apr 25

Frost watch

Sep 22

Reminder workflow

Every date has a next action

Direct sow radishesMar 28

Last frost windowApr 25

First radishes harvest windowApr 25

Last radishes sowing targetSep 22

Signal	Value	Why it matters
Last frost estimate	April 25, 2026	Warm-season transplant risk starts falling after this window.
First frost estimate	October 20, 2026	Fall planting counts backward from this date.
Season length	178 days	Longer seasons can support succession crops.
Spacing	1-2 in	Airflow and root space affect yield.
Soil temperature	40 F+	Seeds and transplants stall in cold soil.

GrowZone may earn from qualifying seed or supply links when real affiliate IDs are configured. No monetized links are active without disclosure.

Local data

Why this date changes by ZIP

Chicago frost history and USDA zone 6a shift the safe planting window. GrowZone uses a local representative station instead of one national rule.

University of Illinois Extension is the kind of local source to verify against when a crop is expensive, weather is unusual, or your yard has a cold pocket.

Crop note

Radishes timing notes

Fast crop; harvest promptly before roots get woody. Radishes prefers full sun, 1-2 in spacing, and soil near 40 F+.

For fall, count backward from Oct 20. A conservative last sowing target is around Sep 22.