When to plant onion in Kyoto
Onion is cold-hardy, so every date keys off Kyoto's frost dates of Apr 1.
Step 1 · Sow
Start seeds indoors
Jan 21 – Feb 11
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 11 – Apr 1
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 9 – Jun 29
Picking runs until conditions turn against the crop.
Window
Days to maturity
90 – 110 d
Kyoto's 241-day season leaves this much room.
Onion on Kyoto'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 1
NOV 28
Common questions
When will onion be ready to harvest in Kyoto?
Expect to harvest from around early June (Jun 9–Jun 29) in Kyoto, based on its local frost dates. Confidence 74%.
When should I start onion seeds indoors in Kyoto?
Start seeds indoors around late January (Jan 21–Feb 11) in Kyoto, based on its local frost dates. Confidence 78%.
When can I transplant onion outdoors in Kyoto?
Transplant outdoors around mid March (Mar 11–Apr 1) in Kyoto, based on its local frost dates. Confidence 82%.
How long is the growing season in Kyoto?
Kyoto has roughly 241 frost-free days, which is enough time to grow onion to maturity outdoors.
The rule of thumb
Sow onion 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 Kyoto's frost dates.
Confidence 82/100 · NOAA GHCN-Daily · 1991–2020 normals · frost dates are probabilities, not guarantees.