Frost dates for Ottawa

◇ Station-based · 89/100 confidence

Last spring frost · safe

May 11

~10% frost risk · typical Apr 29

First fall frost · safe

Sep 29

~10% frost risk · typical Oct 8

Frost-free days

161

Apr 29 → Oct 8

Climate zone

Continental, warm summer

Köppen Dfb

The 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

GROWING SEASON — 161 DAYS

APR 29

OCT 8