When to plant broccoli in Cologne
Broccoli is cold-hardy, so every date keys off Cologne's frost dates of Mar 26.
Step 1 · Sow
Start seeds indoors
Feb 12 – Mar 5
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 12 – Apr 2
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
May 11 – Jun 5
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Aug 3 – Aug 17
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Oct 9 – Nov 3
Maturity window for the second sowing.
Window
Days to maturity
60 – 85 d
Cologne's 238-day season leaves this much room.
Broccoli 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
MAR 26
NOV 17
Common questions
When will broccoli be ready to harvest in Cologne?
Expect to harvest from around mid May (May 11–Jun 5) in Cologne, based on its local frost dates. Confidence 80%.
When should I start broccoli seeds indoors in Cologne?
Start seeds indoors around mid February (Feb 12–Mar 5) in Cologne, based on its local frost dates. Confidence 85%.
When can I transplant broccoli outdoors in Cologne?
Transplant outdoors around mid March (Mar 12–Apr 2) in Cologne, based on its local frost dates. Confidence 89%.
Can I plant broccoli in autumn in Cologne?
Yes — Cologne supports a second, autumn sowing of broccoli around early August (Aug 3–Aug 17), timed to mature before the first fall frost.
How long is the growing season in Cologne?
Cologne has roughly 238 frost-free days, which is enough time to grow broccoli to maturity outdoors.
The rule of thumb
Sow broccoli 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 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.