When to plant radish in Portland
Radish is cold-hardy, so every date keys off Portland's frost dates of Mar 1.
Step 1 · Sow
Direct sow outdoors
Dec 26 – Jan 16
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Jan 20 – Jan 25
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Oct 2 – Oct 16
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Nov 3 – Nov 8
Maturity window for the second sowing.
Window
Days to maturity
25 – 30 d
Portland's 266-day season leaves this much room.
Radish on Portland'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 1
NOV 22
Common questions
When can I sow radish outdoors in Portland?
Direct-sow around late December (Dec 26–Jan 16) in Portland, based on its local frost dates. Confidence 85%.
When will radish be ready to harvest in Portland?
Expect to harvest from around mid January (Jan 20–Jan 25) in Portland, based on its local frost dates. Confidence 79%.
Can I plant radish in autumn in Portland?
Yes — Portland supports a second, autumn sowing of radish around early October (Oct 2–Oct 16), timed to mature before the first fall frost.
How long is the growing season in Portland?
Portland has roughly 266 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 Portland's frost dates.
Confidence 88/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.