Growing zones · Westlock
Westlock growing zone: zone 3b
Westlock, Alberta is in plant hardiness zone 3b on the current Natural Resources Canada map (4th edition, based on 1991–2020 climate normals). The average last spring frost is around June 2 and the first fall frost around August 29, giving about 87 frost-free days at Campsie, 53 km away (the nearest station with frost records, so treat it as indicative).
Planting, hardiness and grow zone in Westlock
"Growing zone", "planting zone" and "hardiness zone" all refer to the same thing in Canada: the plant hardiness zone, which predicts which perennials, trees and shrubs survive the winter. It does not tell you when to plant vegetables; frost dates do that.
Zone 3 covers most of central and northern settled Alberta. Prairie-bred fruit does well; tender perennials need protection.
- Haskap, saskatoon, raspberry and currants
- Sour cherries and hardy plums bred for the prairies
- Prairie-hardy apples such as Norland and Goodland on hardy rootstock
- Spruce, poplar, green ash and caragana for shelterbelts
- Cool-season vegetables; tomatoes and squash after the last frost, often started indoors
Buy perennials rated for zone 3b or colder. Cold-air pockets, low ground and exposed sites in and around Westlock can run a full zone colder than the map.
Frost dates near Westlock
Average dates from Environment and Climate Change Canada's 1991–2020 climate normals at the stations nearest Westlock. Stations in towns usually show a longer season than open farmland nearby, which is why the numbers differ: nearby stations range from 77 to 87 frost-free days.
| Station | Distance | Last spring frost | First fall frost | Frost-free days |
|---|---|---|---|---|
| Campsie | 53 km | June 2 | August 29 | 87 |
| Cross Lake | 54 km | June 10 | August 27 | 77 |
Growing degree-days above 5 °C average about 1,321 a year at Campsie (53 km), and total precipitation about 462 mm at Campsie (53 km).
When to plant in Westlock
- Cool-season crops (peas, spinach, lettuce, radish, potatoes) can go in a few weeks before the last frost, once the soil can be worked.
- Frost-tender crops (tomatoes, peppers, squash, beans, cucumbers) go out after the last frost, around June 2 on average, and many local gardeners wait an extra week.
- Trees, shrubs and perennials rated zone 3b or colder can be planted in spring or early fall.
Common questions
What growing zone is Westlock, Alberta?
Westlock is in Canadian plant hardiness zone 3b on Natural Resources Canada's current map (4th edition, 1991–2020 climate normals). Average frost dates there are about June 2 (last spring frost) and August 29 (first fall frost).
When is the last frost in Westlock?
On average around June 2, based on Environment Canada's 1991–2020 normals at Campsie. Frost can come later in low spots and in cold years, so many gardeners wait about a week past the average before planting tender crops.
Is Westlock zone 3b on the USDA map?
Not necessarily. The USDA map uses only the average coldest winter temperature, while the Canadian map also weighs frost-free days, rain, snow cover and wind, so the two numbers often differ by about half a zone. Check which system a plant label uses.
Nearby places: Barrhead (3a) · Morinville (3b) · St. Albert (4a) · Fort Saskatchewan (3b) · Spruce Grove (4a) · Stony Plain (4a)
Land around Westlock: Westlock County farm guide · Westlock County hardiness zone · all Alberta growing zones · Canadian vs USDA zones explained
Sources: Natural Resources Canada, Plant Hardiness Zones of Canada (4th edition, 1991–2020); Environment and Climate Change Canada, Canadian Climate Normals 1991–2020. Page reviewed 2026-10-08.