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When to Plant Peas in Banff-Jasper, AB

Peas are a cool-season legume that fixes nitrogen in the soil. Garden peas are shelled, while snap and snow peas are eaten pod and all.

Banff-Jasper, Alberta is in USDA Zone 4a. The average last spring frost is May 17 and the first fall frost is October 4, giving you a growing season of approximately 140 days.

At an elevation of 4,537 feet, Banff-Jasper receives approximately 20.6 inches of rainfall annually with predominantly dark brown chernozem soil. Summer highs average 70°F, so choose short-season varieties of Peas to ensure they mature before fall.

Banff-Jasper, AB (Zone 4a) Short season
140 days
Last Spring Frost May 17
140 growing days
First Fall Frost October 4
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Banff-Jasper Soil Profile

Soil Type

Dark Brown Chernozem

Soil pH

6.0-7.0

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5
Recommended (50%) ✓ Fits season (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5
Safe Start (90%) ✓ Fits season (71 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🍅 Harvest: Jun 10 – Aug 5

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

How to Plant Peas

1"
Planting Depth
4"
Between Plants
18"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 102 gal / 100 sq ft

Monthly Watering Guide for Peas

Peas needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Peas Needs Rainfall You Supplement Action
Jan 0.9" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 2" 0" ❄️ Dormant
May 3" 2.5" 0.5" 💧 Light watering
Jun 3" 2.3" 0.7" 💧 Light watering
Jul 3" 2.5" 0.5" 💧 Light watering
Aug 3" 2.4" 0.6" 💧 Light watering
Sep 3" 2" 1" 💧 Light watering
Oct 3" 1.6" 1.4" 💧 Light watering
Nov 1.3" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Banff-Jasper). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Peas Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Peas needs ~156 GDD — county provides 350 GDD Excellent fit

Peas Planting Timeline — Banff-Jasper, AB

Peas Planting Calendar

Activity When Date Range
Start Indoors April 5 Apr 5 – Apr 19
Transplant Outdoors May 17 May 17 – May 31
Direct Sow May 10 May 10 – May 31
Harvest July 12 Jul 12 – Sep 6
Fall Sowing July 12 Jul 12 – Jul 26

Plant 1" deep · 4" apart · Rows 18" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Transplant Outdoors Direct Sow
June
July Fall Sowing Harvest
August Harvest
September Harvest
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

55–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 4a

📆 Growing Season

140 days in Banff-Jasper

Growing Tips for Peas in Banff-Jasper

Common pests for Peas in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow as early as soil can be worked in spring. Inoculate seeds with rhizobium for best nitrogen fixation. Provide trellising for climbing varieties.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Peas Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let pods dry brown and papery on the vine.
Storage Store airtight; viable 3 years at 35°F, under 45% humidity.

Very easy to save. Self-pollinating means varieties stay true.

Frequently Asked Questions

When should I plant Peas in Banff-Jasper, AB?

Banff-Jasper is in Zone 4a with an average last frost of May 17. Plan your Peas planting based on this frost date — see the calendar above for exact timing.

What planting zone is Banff-Jasper, AB?

Banff-Jasper, Alberta is in USDA Hardiness Zone 4a. The average last spring frost is May 17 and first fall frost is October 4.

🌱

Your Banff-Jasper Garden Planner — Free

A 24-page printable planner built for Banff-Jasper (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Banff-Jasper, AB. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.