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When to Plant Mustard Greens in Chelan County, WA

Chelan County, Washington Zone 7a May

May to-do list for Chelan County, Washington

A quick May briefing for Chelan County, Washington gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 24
Avg. first frost October 20
Soil temp (4") 54°F
Watering Critical
Pest pressure Low
Daylight 14.9 hrs
  1. Start mustard greens under lights

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Pick mustard greens

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Looking ahead to June
  • First harvests: mustard greens

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Mustard greens are fast-growing brassicas with a spicy, peppery kick. They come in green, red, and purple varieties and are excellent cooked or in salads.

Chelan County, Washington is in USDA Zone 7a. 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 87°F, providing good warmth for Mustard Greens during the growing season. With low rainfall, drip irrigation is essential for growing Mustard Greens successfully. Mulch heavily to conserve soil moisture.

Chelan County, WA (Zone 7a) 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 (82 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: May 18 – Jul 20
Recommended (50%) ✓ Fits season (81 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: May 29 – Jul 31
Safe Start (90%) ✓ Fits season (72 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 23 – Aug 25

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 Mustard Greens's growing requirements.

Soil pH

Your soil pH (5.5–6.3) is more acidic than Mustard Greens prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Chelan County is excellent for Mustard Greens — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (5.1%) — Mustard Greens will thrive.

How to Plant Mustard Greens

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

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

Succession Planting Mustard Greens

7
successive plantings in your 179-day season

Sow every 3.4 weeks. Last sowing by Aug 31 to harvest before frost.

For a dedicated fall crop, sow by Aug 11.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.3″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 701 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Mustard Greens

Mustard Greens needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Mustard Greens Needs Rainfall You Supplement Action
Jan 2.1" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 1.2" 0" ❄️ Dormant
Apr 3" 1.2" 1.8" 🚿 Regular watering
May 3" 0.9" 2.1" 🚿 Regular watering
Jun 3" 0.6" 2.4" 🚿 Regular watering
Jul 3" 0.2" 2.8" 🚿 Regular watering
Aug 3" 0.3" 2.7" 🚿 Regular watering
Sep 3" 0.5" 2.5" 🚿 Regular watering
Oct 3" 1.2" 1.8" 🚿 Regular watering
Nov 1.9" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Chelan County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Mustard Greens 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" — every day above 50°F 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.

Mustard Greens needs ~610 GDD — county provides 2,729 GDD Excellent fit

Mustard Greens Planting Timeline — Chelan County, WA

Mustard Greens Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 10 Apr 10 – May 1
Harvest May 29 May 29 – Jul 31
Fall Sowing August 11 Aug 11 – Aug 25

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.7"/week · 1-2 times/week

📅 Days to Maturity

30–50 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 7a

📆 Growing Season

179 days in Chelan County

Growing Tips for Mustard Greens in Chelan County

Direct sow Mustard Greens 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 Mustard Greens. Sow every 15.0 days for continuous harvest.

Common pests for Mustard Greens in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in early spring or fall. Harvest young leaves for milder flavor. Plants bolt quickly in heat so grow as a cool-season crop or provide shade.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Mustard Greens in Chelan County, WA?

Chelan County is in Zone 7a with an average last frost of April 24. Plan your Mustard Greens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Chelan County, WA?

Chelan County, Washington is in USDA Hardiness Zone 7a. The average last spring frost is April 24 and first fall frost is October 20.

🌱

Your Chelan County Garden Planner — Free

A 24-page printable planner built for Chelan County (Zone 7a). 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 Chelan County, WA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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