When to plant radish in Sapporo
Radish is cold-hardy, so every date keys off Sapporo's frost dates of May 12.
Step 1 · Sow
Direct sow outdoors
May 1 – May 22
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
May 26 – May 31
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Aug 30 – Sep 13
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Oct 1 – Oct 6
Maturity window for the second sowing.
Window
Days to maturity
25 – 30 d
Sapporo's 166-day season leaves this much room.
Radish on Sapporo'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 12
OCT 20
Common questions
When can I sow radish outdoors in Sapporo?
Direct-sow around early May (May 1–May 22) in Sapporo, based on its local frost dates. Confidence 44%.
When will radish be ready to harvest in Sapporo?
Expect to harvest from around late May (May 26–May 31) in Sapporo, based on its local frost dates. Confidence 40%.
Can I plant radish in autumn in Sapporo?
Yes — Sapporo supports a second, autumn sowing of radish around late August (Aug 30–Sep 13), timed to mature before the first fall frost.
How long is the growing season in Sapporo?
Sapporo has roughly 166 frost-free days, which is enough time to grow radish to maturity outdoors.
The rule of thumb
Sow radish 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 Sapporo's frost dates.
Confidence 45/100 · Curated · based on NASA POWER (modeled) 1991–2020 · frost dates are probabilities, not guarantees.