When to plant summer squash / zucchini in Bismarck
Summer squash / Zucchini is frost-tender, so every date keys off Bismarck's last spring frost of May 15.
Step 1 · Sow
Start seeds indoors
May 14 – Jun 4
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Jun 7 – Jun 28
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jul 22 – Aug 6
Picking runs until conditions turn against the crop.
Window
Days to maturity
45 – 60 d
Bismarck's 132-day season leaves this much room.
Summer squash / Zucchini on Bismarck's growing year
Frost-bounded season with crops mapped onto the 12-month axis.
Frost risk Growing Harvest
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
FROST
FROST
MAY 15
SEP 25
Common questions
When can I sow summer squash / zucchini outdoors in Bismarck?
Direct-sow around early June (Jun 7–Jun 28) in Bismarck, based on its local frost dates. Confidence 86%.
When will summer squash / zucchini be ready to harvest in Bismarck?
Expect to harvest from around late July (Jul 22–Aug 6) in Bismarck, based on its local frost dates. Confidence 80%.
When should I start summer squash / zucchini seeds indoors in Bismarck?
Start seeds indoors around mid May (May 14–Jun 4) in Bismarck, based on its local frost dates. Confidence 85%.
When can I transplant summer squash / zucchini outdoors in Bismarck?
Transplant outdoors around early June (Jun 7–Jun 28) in Bismarck, based on its local frost dates. Confidence 86%.
How long is the growing season in Bismarck?
Bismarck has roughly 132 frost-free days, which is enough time to grow summer squash / zucchini to maturity outdoors.
The rule of thumb
Sow summer squash / zucchini 6–8 weeks before your last spring frost; plant out 2–3 weeks after it. Every date on this page is derived from that rule and Bismarck's frost dates.
Confidence 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.