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When to Plant Amaranth in Sarnia-Lambton, ON

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.

Sarnia-Lambton, Ontario is in USDA Zone 7b. The average last spring frost is April 3 and the first fall frost is October 27, giving you a growing season of approximately 207 days.

At an elevation of 590 feet, Sarnia-Lambton receives approximately 39.1 inches of rainfall annually with predominantly clay loam soil. Summer highs average 84°F, so choose short-season varieties of Amaranth to ensure they mature before fall. Clay soil retains moisture well for Amaranth, but amend with compost to improve drainage and prevent root rot.

Sarnia-Lambton, ON (Zone 7b) Long season
207 days
Last Spring Frost April 3
207 growing days
First Fall Frost October 27

Sarnia-Lambton Soil Profile

Soil Type

Clay Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Amaranth Planting Timeline — Sarnia-Lambton, ON

Amaranth Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 10 Apr 10 – May 1
Harvest July 17 Jul 17 – Sep 4

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7b

📆 Growing Season

207 days in Sarnia-Lambton

Growing Tips for Sarnia-Lambton

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 Sarnia-Lambton, ON?

Sarnia-Lambton is in Zone 7b with an average last frost of April 3. Plan your Amaranth planting based on this frost date — see the calendar above for exact timing.

What planting zone is Sarnia-Lambton, ON?

Sarnia-Lambton, Ontario is in USDA Hardiness Zone 7b. The average last spring frost is April 3 and first fall frost is October 27.

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A 22-page printable planner built for Sarnia-Lambton (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Sarnia-Lambton, ON. Local conditions may vary. Last updated: July 2026.

Sources & credits

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