Blog

When to Plant Melon in Yakima County, WA

Melons are warm-season vine crops that produce sweet, juicy fruits in many varieties including muskmelon and honeydew. They need a long, hot growing season.

Yakima County, Washington is in USDA Zone 6b. The average last spring frost is May 6 and the first fall frost is October 3, giving you a growing season of approximately 150 days.

At an elevation of 3,150 feet, Yakima County receives approximately 18 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Melon during the growing season. With low rainfall, drip irrigation is essential for growing Melon successfully. Mulch heavily to conserve soil moisture.

Yakima County, WA (Zone 6b) Moderate season
150 days
Last Spring Frost May 6
150 growing days
First Fall Frost October 3

Yakima 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 (17 days to spare)
Start indoors: Mar 26 Transplant: May 14 🍅 Harvest: Jul 23 – Sep 10
Recommended (50%) ✓ Fits season (17 days to spare)
Start indoors: Apr 1 Transplant: May 20 🍅 Harvest: Jul 29 – Sep 16
Safe Start (90%) ✓ Fits season (14 days to spare)
Start indoors: Apr 21 Transplant: Jun 9 🍅 Harvest: Aug 18 – Oct 6

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 662 gal / 100 sq ft
Melon needs ~1,232 GDD — county provides 2,175 GDD Excellent fit

Melon Planting Timeline โ€” Yakima County, WA

Melon Planting Calendar

Activity When Date Range
Start Indoors April 1 Apr 1 โ€“ Apr 15
Transplant Outdoors May 20 May 20 โ€“ Jun 3
Direct Sow May 13 May 13 โ€“ Jun 3
Harvest July 29 Jul 29 โ€“ Sep 16

Plant 1" deep ยท 30" apart ยท Rows 42" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

70โ€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

150 days

Growing Tips for Yakima County

Start seeds indoors 3-4 weeks before transplanting. Plant on raised mounds of compost-enriched soil. Reduce watering as fruits ripen to concentrate sweetness.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes
  • Cucumber

Level Up Your Garden

Frequently Asked Questions

When should I plant Melon in Yakima County, WA?

Yakima County is in Zone 6b with an average last frost of May 6. Plan your Melon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Yakima County, WA?

Yakima County, Washington is in USDA Hardiness Zone 6b. The average last spring frost is May 6 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Yakima County gardeners in Zone 6b 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 Yakima County, WA. Local conditions may vary. Last updated: April 2026.