When to plant radish in Knoxville
Radish is cold-hardy, so every date keys off Knoxville's frost dates of Apr 8.
Step 1 · Sow
Direct sow outdoors
Mar 11 – Apr 1
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Apr 5 – Apr 10
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Sep 7 – Sep 21
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Oct 9 – Oct 14
Maturity window for the second sowing.
Window
Days to maturity
25 – 30 d
Knoxville's 201-day season leaves this much room.
Radish on Knoxville'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 8
OCT 28
Common questions
When can I sow radish outdoors in Knoxville?
Direct-sow around mid March (Mar 11–Apr 1) in Knoxville, based on its local frost dates. Confidence 89%.
When will radish be ready to harvest in Knoxville?
Expect to harvest from around early April (Apr 5–Apr 10) in Knoxville, based on its local frost dates. Confidence 80%.
Can I plant radish in autumn in Knoxville?
Yes — Knoxville supports a second, autumn sowing of radish around early September (Sep 7–Sep 21), timed to mature before the first fall frost.
How long is the growing season in Knoxville?
Knoxville has roughly 201 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 Knoxville's frost dates.
Confidence 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.