When to plant onion in Halifax
Onion is cold-hardy, so every date keys off Halifax's frost dates of May 13.
Step 1 · Sow
Start seeds indoors
Mar 4 – Mar 25
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 26 – Jun 16
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Aug 24 – Sep 13
Picking runs until conditions turn against the crop.
Window
Days to maturity
90 – 110 d
Halifax's 158-day season leaves this much room.
Onion on Halifax'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
MAY 13
OCT 20
Common questions
When will onion be ready to harvest in Halifax?
Expect to harvest from around late August (Aug 24–Sep 13) in Halifax, based on its local frost dates. Confidence 70%.
When should I start onion seeds indoors in Halifax?
Start seeds indoors around early March (Mar 4–Mar 25) in Halifax, based on its local frost dates. Confidence 74%.
When can I transplant onion outdoors in Halifax?
Transplant outdoors around late May (May 26–Jun 16) in Halifax, based on its local frost dates. Confidence 76%.
How long is the growing season in Halifax?
Halifax has roughly 158 frost-free days, which is enough time to grow onion to maturity outdoors.
The rule of thumb
Sow onion 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 Halifax's frost dates.
Confidence 78/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.