Montana · zones 4a–5b
When to plant zucchini in Montana.
Sow between May 22 to Jul 21 in a typical year, keyed to Montana's median last frost around May 15. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Zucchini dates for a typical Montana season.
Direct sow
May 22 to Jul 21
Keyed to the ~May 15 last frost. Sow 1" deep, 24" apart.
Harvest
~50 days later
~8 lb per plant over ~5 weeks.
Montana spans more than one climate: Zone 4 is the most common zone, but the state runs 4a to 5b. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In Montana: watch for
The pests that find zucchini here.
The short season here, about 131 frost-free days, keeps squash, summer in front of squash bugs only briefly. One early row cover usually carries a planting through the worst of it.
Gray shield bugs; leaves wilt and get crispy patches.
Organic fix: Lay a board out overnight and collect them at dawn; scrape bronze egg clusters off leaf undersides.
Sudden wilt with sawdust-like frass at the stem base.
Organic fix: Cover young plants; slit the stem to remove the grub, or inject Bt.
Yellow striped or spotted beetles chewing leaves and blossoms.
Organic fix: Row cover until the first female flowers open, then hand-pick.
White powder coating the leaves late in the season.
Organic fix: Space for airflow, water the soil rather than the leaves, use resistant varieties.
Your season math: Montana gives zucchini about 131 frost-free days, and it needs roughly 50 days to a first harvest. That fits about 3 re-sown rounds across the season, so you can keep it coming instead of picking once.
Planting zucchini in Montana: questions
When should I plant zucchini in Montana?+
In a typical Montana year, sow zucchini between May 22 to Jul 21, keyed to the state's median last frost around May 15. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Montana?+
Montana spans zones 4a–5b, mostly zone 4. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many zucchini plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.