When to plant leek in New Haven
Leek is cold-hardy, so every date keys off New Haven's frost dates of Apr 19.
Step 1 · Sow
Start seeds indoors
Feb 8 – Mar 1
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Apr 9 – Apr 30
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jul 18 – Aug 7
Picking runs until conditions turn against the crop.
Window
Days to maturity
100 – 120 d
New Haven's 184-day season leaves this much room.
Leek on New Haven'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
APR 19
OCT 19
Common questions
When will leek be ready to harvest in New Haven?
Expect to harvest from around mid July (Jul 18–Aug 7) in New Haven, based on its local frost dates. Confidence 75%.
When should I start leek seeds indoors in New Haven?
Start seeds indoors around early February (Feb 8–Mar 1) in New Haven, based on its local frost dates. Confidence 79%.
When can I transplant leek outdoors in New Haven?
Transplant outdoors around early April (Apr 9–Apr 30) in New Haven, based on its local frost dates. Confidence 81%.
How long is the growing season in New Haven?
New Haven has roughly 184 frost-free days, which is enough time to grow leek to maturity outdoors.
The rule of thumb
Sow leek 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 New Haven's frost dates.
Confidence 83/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.