When to plant swiss chard in Cologne
Swiss chard is cold-hardy, so every date keys off Cologne's frost dates of Apr 20.
Step 1 · Sow
Start seeds indoors
Mar 23 – Apr 13
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Apr 6 – Apr 27
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
May 26 – Jun 5
Picking runs until conditions turn against the crop.
Window
Days to maturity
50 – 60 d
Cologne's 185-day season leaves this much room.
Swiss chard on Cologne'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 20
OCT 22
Common questions
When can I sow swiss chard outdoors in Cologne?
Direct-sow around early April (Apr 6–Apr 27) in Cologne, based on its local frost dates. Confidence 82%.
When will swiss chard be ready to harvest in Cologne?
Expect to harvest from around late May (May 26–Jun 5) in Cologne, based on its local frost dates. Confidence 74%.
When should I start swiss chard seeds indoors in Cologne?
Start seeds indoors around late March (Mar 23–Apr 13) in Cologne, based on its local frost dates. Confidence 78%.
When can I transplant swiss chard outdoors in Cologne?
Transplant outdoors around early April (Apr 6–Apr 27) in Cologne, based on its local frost dates. Confidence 82%.
How long is the growing season in Cologne?
Cologne has roughly 185 frost-free days, which is enough time to grow swiss chard to maturity outdoors.
The rule of thumb
Sow swiss chard 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 Cologne's frost dates.
Confidence 82/100 · NOAA GHCN-Daily · 1991–2020 normals · frost dates are probabilities, not guarantees.