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USDA hardiness zone lookup

Saginaw, MI — USDA Zone 6a

Saginaw, Michigan · 155-day growing season

Frost dates and growing season in Saginaw

USDA hardiness zoneZone 6a
Average last spring frostMay 5
Average first fall frostOctober 7
Growing season length~155 days
Temperature range (F)-10 to 0°F
Temperature range (C)-23 to -18°C

All of Saginaw's mapped ZIP codes fall in the same hardiness band, Zone 6a.

These are 50%-probability averages modeled from Saginaw's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by May 5, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.

Growing season in Saginaw

Saginaw, Michigan sits in USDA Zone 6a, with roughly 155 frost-free days between an average last spring frost around May 5 and a first fall frost around October 7. That is a standard temperate season — most common vegetables finish comfortably, and a single main planting plus one succession round works well.

What grows in Saginaw

Saginaw falls in USDA Zone 6a, so the same hardiness constraints apply as the full Zone 6 guide. Vegetables, herbs, and fruit trees rated to Zone 6a (or hardier) will overwinter here in a typical year.

What to plant in Saginaw this week

Saginaw's last frost is around May 5. This is the spring transplant window — start tomatoes and peppers indoors if you haven't, and direct-sow cold-tolerant crops now.

Full planting calendar for Saginaw

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 6 averages:

ZIP codes in Saginaw

Drill down to the precise frost window and planting calendar for a specific ZIP in Saginaw:

Local microclimate notes

Zone tables give you the average — but Saginawgardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.

Source and methodology

Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Saginaw's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.

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