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When to Plant Amaranth in Chelan County, WA

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.

Chelan County, Washington is in USDA Zone 6a. The average last spring frost is April 24 and the first fall frost is October 20, giving you a growing season of approximately 179 days.

At an elevation of 3,517 feet, Chelan County receives approximately 14.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Amaranth during the growing season. With low rainfall, drip irrigation is essential for growing Amaranth successfully. Mulch heavily to conserve soil moisture.

Chelan County, WA (Zone 6a) Moderate season
179 days
Last Spring Frost April 24
179 growing days
First Fall Frost October 20

Chelan County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (26 days to spare)
Start indoors: Feb 16 Transplant: Apr 27 🍅 Harvest: Jul 27 – Sep 14
Recommended (50%) ✓ Fits season (25 days to spare)
Start indoors: Feb 27 Transplant: May 8 🍅 Harvest: Aug 7 – Sep 25
Safe Start (90%) ✓ Fits season (16 days to spare)
Start indoors: Mar 24 Transplant: Jun 2 🍅 Harvest: Sep 1 – Oct 20

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.

Soil Compatibility in Chelan County

How your county's soil matches Amaranth's growing requirements.

Soil pH

Your soil pH (5.5โ€“6.3) is more acidic than Amaranth prefers (6.0โ€“7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Chelan County is excellent for Amaranth โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.1%) โ€” Amaranth will thrive.

How to Plant Amaranth

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.3″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,275 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 2.1" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 1.2" 0" โ„๏ธ Dormant
Apr 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
May 4.3" 0.9" 3.4" ๐Ÿšฟ Regular watering
Jun 4.3" 0.6" 3.7" ๐Ÿšฟ Regular watering
Jul 4.3" 0.2" 4.1" ๐Ÿšฟ Regular watering
Aug 4.3" 0.3" 4" ๐Ÿšฟ Regular watering
Sep 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
Oct 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
Nov โ€” 1.9" 0" โ„๏ธ Dormant
Dec โ€” 2.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Chelan County). 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 ~1,601 GDD — county provides 2,729 GDD Excellent fit

Amaranth Planting Timeline โ€” Chelan County, WA

Amaranth Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 โ€“ Mar 13
Transplant Outdoors May 8 May 8 โ€“ May 22
Direct Sow May 1 May 1 โ€“ May 22
Harvest August 7 Aug 7 โ€“ Sep 25

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

179 days in Chelan County

Growing Tips for Amaranth in Chelan County

Direct sow Amaranth outdoors after April 24 in Chelan County when soil has warmed and frost danger has passed.

Chelan County receives only 14" 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 Chelan County, WA?

Chelan County is in Zone 6a with an average last frost of April 24. Plan your Amaranth planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Chelan County, WA?

Chelan County, Washington is in USDA Hardiness Zone 6a. The average last spring frost is April 24 and first fall frost is October 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Chelan County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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