When to plant spinach in Missoula
Spinach is cold-hardy, so every date keys off Missoula's frost dates of May 15.
Step 1 · Sow
Direct sow outdoors
Apr 3 – Apr 24
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
May 13 – May 23
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Jul 25 – Aug 8
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Sep 10 – Sep 20
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Missoula's 138-day season leaves this much room.
Spinach on Missoula'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
OCT 4
Common questions
When can I sow spinach outdoors in Missoula?
Direct-sow around early April (Apr 3–Apr 24) in Missoula, based on its local frost dates. Confidence 83%.
When will spinach be ready to harvest in Missoula?
Expect to harvest from around mid May (May 13–May 23) in Missoula, based on its local frost dates. Confidence 75%.
Can I plant spinach in autumn in Missoula?
Yes — Missoula supports a second, autumn sowing of spinach around late July (Jul 25–Aug 8), timed to mature before the first fall frost.
How long is the growing season in Missoula?
Missoula has roughly 138 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 Missoula's frost dates.
Confidence 83/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.