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ZIP 48226 planting calendar

When to plant bush beans in Detroit, MI - Zone 6b

In ZIP 48226, plant bush beans around May 12; this uses the Detroit frost station, USDA zone 6b, and bush beans timing rules.

Your Detroit calendar has a 163-day estimated frost-free season. This estimate uses the representative Detroit frost station, USDA zone 6b, and bush beans timing rules.

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

USDA zone 6b Detroit frost station Michigan State University Extension Updated 2026-06-28
Read the method

Answer first

When to start bush beans seeds indoors in Detroit

In ZIP 48226, bush beans is usually direct-sown around May 12 instead of started indoors.

Bush beans is normally direct-sown in Detroit. Use around May 12 as the outdoor planting window for ZIP 48226.

Seed starting schedule

Bush beans dates for Detroit, MI

StepDateHow to use it
Direct SowMay 12, 2026Sow seed outside when the crop and soil can handle the window.

Last frost

When is the last frost in Detroit?

Detroit (ZIP 48226) has an average last spring frost around May 5.

First frost

When is the first frost in Detroit?

The average first fall frost is around Oct 15, giving about 163 frost-free days.

Season map

Bush beans windows by month

JanFebMarAprMayJunJulAugSepOctNovDec
Direct sow
May 12
Harvest
Jul 6
Frost watch
Aug 21

Reminder workflow

Every date has a next action

Last frost windowMay 5
Direct sow bush beansMay 12
First bush beans harvest windowJul 6
Last bush beans sowing targetAug 21
SignalValueWhy it matters
Last frost estimateMay 5, 2026Warm-season transplant risk starts falling after this window.
First frost estimateOctober 15, 2026Fall planting counts backward from this date.
Season length163 daysLonger seasons can support succession crops.
Spacing4-6 inAirflow and root space affect yield.
Soil temperature60 F+Seeds and transplants stall in cold soil.

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Local data

Why this date changes by ZIP

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

Michigan State University 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

Bush beans timing notes

Wait until soil is warm, then sow every two weeks for a steady crop. Bush beans prefers full sun, 4-6 in spacing, and soil near 60 F+.

For fall, count backward from Oct 15. A conservative last sowing target is around Aug 21.