Planting calendar

When to plant zucchini in Michigan

Michigan spans USDA hardiness zones 4a-6b. Average last spring frost: 05-15. This calendar gives you the indoor start, transplant, and direct-sow dates for Cucurbita pepo.

Michigan planting dates for zucchini

PhaseDate in MichiganNotes
Start seeds indoorsApril 243 weeks before last frost
Transplant outdoorsMay 221 weeks after last frost
Direct sow outsideMay 221 weeks after last frost

Why these dates

Zucchini germinates fast in warm soil. Squash vine borer is the main killer in the eastern US - row covers until flowering, then hand-pick adults in late June.

The dates above are anchored to Michigan's average last spring frost date of 05-15, with offsets standard across university Extension publications. For zone-specific local timing, use the frost date lookup tool with your ZIP code.

More on growing zucchini

The full growing guide for zucchini - varieties, soil, fertilization, pests, harvest, storage - is here: Zucchini growing guide.

More Michigan planting information

Sources