When to plant spinach in Tulsa
Spinach is cold-hardy, so every date keys off Tulsa's frost dates of Mar 31.
Step 1 · Sow
Direct sow outdoors
Dec 25 – Jan 15
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Feb 3 – Feb 13
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Aug 24 – Sep 7
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Oct 10 – Oct 20
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Tulsa's 214-day season leaves this much room.
Spinach on Tulsa'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
MAR 31
NOV 3
Common questions
When can I sow spinach outdoors in Tulsa?
Direct-sow around late December (Dec 25–Jan 15) in Tulsa, based on its local frost dates. Confidence 85%.
When will spinach be ready to harvest in Tulsa?
Expect to harvest from around early February (Feb 3–Feb 13) in Tulsa, based on its local frost dates. Confidence 79%.
Can I plant spinach in autumn in Tulsa?
Yes — Tulsa supports a second, autumn sowing of spinach around late August (Aug 24–Sep 7), timed to mature before the first fall frost.
How long is the growing season in Tulsa?
Tulsa has roughly 214 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 Tulsa's frost dates.
Confidence 88/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.