When to plant spinach in Ottawa
Spinach is cold-hardy, so every date keys off Ottawa's frost dates of Apr 29.
Step 1 · Sow
Direct sow outdoors
Apr 19 – May 10
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
May 29 – Jun 8
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Jul 29 – Aug 12
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Sep 14 – Sep 24
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Ottawa's 161-day season leaves this much room.
Spinach on Ottawa'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
APR 29
OCT 8
Common questions
When can I sow spinach outdoors in Ottawa?
Direct-sow around mid April (Apr 19–May 10) in Ottawa, based on its local frost dates. Confidence 86%.
When will spinach be ready to harvest in Ottawa?
Expect to harvest from around late May (May 29–Jun 8) in Ottawa, based on its local frost dates. Confidence 80%.
Can I plant spinach in autumn in Ottawa?
Yes — Ottawa supports a second, autumn sowing of spinach around late July (Jul 29–Aug 12), timed to mature before the first fall frost.
How long is the growing season in Ottawa?
Ottawa has roughly 161 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 Ottawa's frost dates.
Confidence 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.