Skip to content
EveryOrchard
Menu

Location almanac

Chill hours in T4B

The short answer

T4B averages 1,405 chill hours per winter (9531,641 across 10 years) in USDA zone 4a.
T4B climate
Average chill hours1,405 (953–1,641 across 10 winters)
USDA hardiness zone4a (NRCan zone 3b)
Last spring frosttypically April 26 – May 21
First fall frosttypically September 17 – October 22

Computed from 10 winters of ERA5 hourly temperature (Open-Meteo, 2015–2025); zones from USDA PHZM 2023 / NRCan 1981–2010. Data updated July 3, 2026. See methodology.

Every variety in our database, checked against T4B’s chill hours and zone:

How many chill hours does T4B get?
T4B averages 1405 chill hours per winter, ranging from 953 to 1641 across the last 10 years.
What hardiness zone is T4B?
T4B is in USDA hardiness zone 4a.

Growing fruit trees in T4B? Get a care calendar anchored to this exact climate, with email reminders.

Start My Orchard

Sources

  1. [1] Open-Meteo / Copernicus ERA5. Historical Weather API (hourly 2m temperature) — accessed July 2026
  2. [2] Natural Resources Canada. Plant Hardiness Zones of Canada — accessed July 2026