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When to Plant Amaranth in Banff-Jasper, AB

Amaranth is an ancient grain crop with edible leaves and seeds, rich in protein and micronutrients. It thrives in warm conditions and is drought-tolerant once established.

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 70ยฐF, so choose short-season varieties of Amaranth 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

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 (22 days to spare)
Start indoors: Feb 11 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 23
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Feb 11 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 23
Safe Start (90%) ✓ Fits season (22 days to spare)
Start indoors: Feb 11 Transplant: May 6 🍅 Harvest: Aug 5 – Sep 23

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 Amaranth

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 476 gal / 100 sq ft

Monthly Watering Guide for Amaranth

Amaranth needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Amaranth Needs Rainfall You Supplement Action
Jan โ€” 0.9" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 1.2" 0" โ„๏ธ Dormant
Apr โ€” 2" 0" โ„๏ธ Dormant
May 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Jun 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Jul 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Aug 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Sep 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Oct 4.3" 1.6" 2.7" ๐Ÿšฟ Regular watering
Nov โ€” 1.3" 0" โ„๏ธ Dormant
Dec โ€” 1.1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Banff-Jasper). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Amaranth 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" โ€” every day above 50ยฐF 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.

Amaranth needs ~262 GDD — county provides 350 GDD Excellent fit

Amaranth Planting Timeline โ€” Banff-Jasper, AB

Amaranth Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 โ€“ Mar 29
Transplant Outdoors June 7 Jun 7 โ€“ Jun 21
Direct Sow May 31 May 31 โ€“ Jun 21
Harvest September 6 Sep 6 โ€“ Oct 25

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April โ€”
May Direct Sow
June Transplant Outdoors Direct Sow
July โ€”
August โ€”
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

140 days in Banff-Jasper

Growing Tips for Amaranth in Banff-Jasper

Banff-Jasper receives only 21" of rain annually. Amaranth needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost when soil is warm. Thin seedlings to 18 inches apart. Harvest leaves when young and tender; harvest seeds when flower heads begin to dry.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

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

Banff-Jasper is in Zone 4a with an average last frost of May 17. Plan your Amaranth planting based on this frost date โ€” 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.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Banff-Jasper gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

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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: April 2026.