When to plant sweet corn in San Jose
Sweet corn is frost-tender, so every date keys off San Jose's last spring frost of Feb 12.
Step 1 · Sow
Direct sow outdoors
May 10 – May 31
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Jul 9 – Aug 18
Picking runs until conditions turn against the crop.
Window
Days to maturity
60 – 100 d
San Jose's 294-day season leaves this much room.
Sweet corn on San Jose'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
HARVEST
FEB 12
DEC 3
Common questions
When can I sow sweet corn outdoors in San Jose?
Direct-sow around early May (May 10–May 31) in San Jose, based on its local frost dates. Confidence 80%.
When will sweet corn be ready to harvest in San Jose?
Expect to harvest from around early July (Jul 9–Aug 18) in San Jose, based on its local frost dates. Confidence 74%.
How long is the growing season in San Jose?
San Jose has roughly 294 frost-free days, which is enough time to grow sweet corn to maturity outdoors.
The rule of thumb
Sow sweet corn 6–8 weeks before your last spring frost; plant out 2–3 weeks after it. Every date on this page is derived from that rule and San Jose's frost dates.
Confidence 82/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.