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When to Plant Microgreens in Chelan County, WA

Microgreens are young seedlings of vegetables and herbs harvested at the cotyledon or first true leaf stage. They pack concentrated flavors and nutrients in a tiny package.

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 Microgreens during the growing season. With low rainfall, drip irrigation is essential for growing Microgreens 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 (145 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Apr 20 – May 18
Recommended (50%) ✓ Fits season (144 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: May 1 – May 29
Safe Start (90%) ✓ Fits season (135 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: May 26 – Jun 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.

Soil Compatibility in Chelan County

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

Soil pH

Your soil pH (5.5โ€“6.3) is more acidic than Microgreens prefers (6.0โ€“7.0). Add garden lime to raise pH.

Soil Texture

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

Organic Matter

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

How to Plant Microgreens

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Microgreens

35
successive plantings in your 179-day season

Sow every 0.7 weeks. Last sowing by Sep 29 to harvest before frost.

For a dedicated fall crop, sow by Aug 11.

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 Microgreens

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

Month Microgreens 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.

Microgreens 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.

Microgreens needs ~214 GDD — county provides 2,729 GDD Excellent fit

Microgreens Planting Timeline โ€” Chelan County, WA

Microgreens Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 โ€“ Apr 3
Transplant Outdoors April 24 Apr 24 โ€“ May 8
Direct Sow April 10 Apr 10 โ€“ May 1
Harvest May 1 May 1 โ€“ May 29
Fall Sowing August 11 Aug 11 โ€“ Aug 25

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

7โ€“21 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

179 days in Chelan County

Growing Tips for Microgreens in Chelan County

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

Your generous 179.0-day season in Chelan County allows multiple plantings of Microgreens. Sow every 3.0 days for continuous harvest.

Chelan County receives only 14" of rain annually. Microgreens needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Sow seeds densely on shallow trays of moist growing medium. Cover until germination, then provide light. Harvest with scissors when 1-3 inches tall. Grow year-round indoors.

Frequently Asked Questions

When should I plant Microgreens in Chelan County, WA?

Chelan County is in Zone 6a with an average last frost of April 24. Plan your Microgreens 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.