When to plant spinach in Bismarck
Spinach is cold-hardy, so every date keys off Bismarck's frost dates of May 15.
Step 1 · Sow
Direct sow outdoors
Apr 16 – May 7
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
May 26 – Jun 5
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Jul 16 – Jul 30
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Sep 1 – Sep 11
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Bismarck's 132-day season leaves this much room.
Spinach 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 spinach outdoors in Bismarck?
Direct-sow around mid April (Apr 16–May 7) in Bismarck, based on its local frost dates. Confidence 86%.
When will spinach be ready to harvest in Bismarck?
Expect to harvest from around late May (May 26–Jun 5) in Bismarck, based on its local frost dates. Confidence 80%.
Can I plant spinach in autumn in Bismarck?
Yes — Bismarck supports a second, autumn sowing of spinach around mid July (Jul 16–Jul 30), timed to mature before the first fall frost.
How long is the growing season in Bismarck?
Bismarck has roughly 132 frost-free days, which is enough time to grow spinach to maturity outdoors.
The rule of thumb
Sow spinach as soon as the soil is workable — it tolerates cool weather and light frost. 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.