When to plant swiss chard in London

Swiss chard is cold-hardy, so every date keys off London's frost dates of Apr 6.
Step 1 · Sow
Start seeds indoors
Mar 9 – Mar 30
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 23 – Apr 13
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
May 12 – May 22
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Aug 7 – Aug 21
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Oct 3 – Oct 13
Maturity window for the second sowing.
Window
Days to maturity
50 – 60 d
London's 234-day season leaves this much room.
Swiss chard on London'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
APR 6
NOV 16

Common questions

When can I sow swiss chard outdoors in London?

Direct-sow around late March (Mar 23–Apr 13) in London, based on its local frost dates. Confidence 82%.

When will swiss chard be ready to harvest in London?

Expect to harvest from around mid May (May 12–May 22) in London, based on its local frost dates. Confidence 74%.

When should I start swiss chard seeds indoors in London?

Start seeds indoors around early March (Mar 9–Mar 30) in London, based on its local frost dates. Confidence 78%.

When can I transplant swiss chard outdoors in London?

Transplant outdoors around late March (Mar 23–Apr 13) in London, based on its local frost dates. Confidence 82%.

Can I plant swiss chard in autumn in London?

Yes — London supports a second, autumn sowing of swiss chard around early August (Aug 7–Aug 21), timed to mature before the first fall frost.

How long is the growing season in London?

London has roughly 234 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 London's frost dates.

Confidence 82/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.