When to plant swiss chard in St. Louis

Swiss chard is cold-hardy, so every date keys off St. Louis's frost dates of Mar 30.
Step 1 · Sow
Start seeds indoors
Mar 2 – Mar 23
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 17 – Apr 7
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
May 6 – May 16
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Aug 6 – Aug 20
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Oct 2 – Oct 12
Maturity window for the second sowing.
Window
Days to maturity
50 – 60 d
St. Louis's 218-day season leaves this much room.
Swiss chard on St. Louis'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
MAR 30
NOV 5

Common questions

When can I sow swiss chard outdoors in St. Louis?

Direct-sow around mid March (Mar 17–Apr 7) in St. Louis, based on its local frost dates. Confidence 81%.

When will swiss chard be ready to harvest in St. Louis?

Expect to harvest from around early May (May 6–May 16) in St. Louis, based on its local frost dates. Confidence 76%.

When should I start swiss chard seeds indoors in St. Louis?

Start seeds indoors around early March (Mar 2–Mar 23) in St. Louis, based on its local frost dates. Confidence 80%.

When can I transplant swiss chard outdoors in St. Louis?

Transplant outdoors around mid March (Mar 17–Apr 7) in St. Louis, based on its local frost dates. Confidence 81%.

Can I plant swiss chard in autumn in St. Louis?

Yes — St. Louis supports a second, autumn sowing of swiss chard around early August (Aug 6–Aug 20), timed to mature before the first fall frost.

How long is the growing season in St. Louis?

St. Louis has roughly 218 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 St. Louis's frost dates.

Confidence 84/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.