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When to Plant Amaranth in USDA Zone 5b

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.

In Zone 5b, the average last spring frost is around April 18 and the first fall frost is around October 13, giving you a growing season of approximately 178 days.

Zone 5b Moderate season
178 days
Last Spring Frost April 18
178 growing days
First Fall Frost October 13

Amaranth Planting Timeline — Zone 5b

Where Is USDA Zone 5b?

The map below highlights the states that contain Zone 5b. Click any state to see the Amaranth planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Amaranth Planting Calendar — Zone 5b

Activity When Date Range
Start Indoors February 21 Feb 21 – Mar 7
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest August 1 Aug 1 – Sep 19

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

Month-by-Month Timeline

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

Free Zone 5b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

90–120 days

Soil pH

6 – 7.5

Zone Temperature Range

-15°F to -10°F average annual minimum

Growing Season

178 days (Zone 5b average)

Planting Specifications

Planting Depth1 inches
Plant Spacing15 inches apart
Row Spacing24 inches between rows

Growing Tips for Amaranth in Zone 5b

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

Level Up Your Garden

Saving Amaranth Seeds

Recommended for Your Garden

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

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Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

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Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Amaranth in Zone 5b?

In Zone 5b, plan your Amaranth planting around the average last frost date of April 18. Start seeds indoors around February 21. Direct sow outdoors around April 25. Transplant seedlings around May 2.

Can Amaranth grow in Zone 5b?

Yes, Amaranth can grow well in Zone 5b, hardy in USDA zones 2a through 11b. Zone 5b has a growing season of approximately 178 days, which is sufficient for Amaranth (90-120 days to maturity).

When can I harvest Amaranth in Zone 5b?

In Zone 5b, expect to harvest Amaranth from August 1 – September 19. Amaranth takes 90-120 days from planting to harvest.

What is the last frost date for Zone 5b?

The average last spring frost in Zone 5b is around April 18, and the first fall frost is around October 13. This gives a growing season of approximately 178 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Amaranth?

Good companion plants for Amaranth include Corn, Tomatoes, Eggplant. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 5b, track your crops, and plan your garden season from seed to harvest.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.