When to plant spinach in Riverside
Spinach is cold-hardy, so every date keys off Riverside's frost dates of Feb 16.
Step 1 · Sow
Direct sow outdoors
Jan 5 – Jan 26
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Feb 14 – Feb 24
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Sep 26 – Oct 10
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Nov 12 – Nov 22
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Riverside's 293-day season leaves this much room.
Spinach on Riverside'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
FEB 16
DEC 6
Common questions
When can I sow spinach outdoors in Riverside?
Direct-sow around early January (Jan 5–Jan 26) in Riverside, based on its local frost dates. Confidence 78%.
When will spinach be ready to harvest in Riverside?
Expect to harvest from around mid February (Feb 14–Feb 24) in Riverside, based on its local frost dates. Confidence 70%.
Can I plant spinach in autumn in Riverside?
Yes — Riverside supports a second, autumn sowing of spinach around late September (Sep 26–Oct 10), timed to mature before the first fall frost.
How long is the growing season in Riverside?
Riverside has roughly 293 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 Riverside's frost dates.
Confidence 78/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.