When to plant sweet corn in Christchurch
Sweet corn is frost-tender, so every date keys off Christchurch's last spring frost of Oct 16.
Step 1 · Sow
Direct sow outdoors
Dec 21 – Jan 11
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Feb 19 – Mar 31
Picking runs until conditions turn against the crop.
Window
Days to maturity
60 – 100 d
Christchurch's 211-day season leaves this much room.
Sweet corn on Christchurch'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
OCT 16
MAY 19
Common questions
When can I sow sweet corn outdoors in Christchurch?
Direct-sow around late December (Dec 21–Jan 11) in Christchurch, based on its local frost dates. Confidence 44%.
When will sweet corn be ready to harvest in Christchurch?
Expect to harvest from around mid February (Feb 19–Mar 31) in Christchurch, based on its local frost dates. Confidence 40%.
How long is the growing season in Christchurch?
Christchurch has roughly 211 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 Christchurch's frost dates.
Confidence 45/100 · Curated · based on NASA POWER (modeled) 1991–2020 · frost dates are probabilities, not guarantees.