Blog

When to Plant Honeydew in Whitman County, WA

Honeydew melons have smooth, pale green rinds and sweet, light green flesh. They require a long, warm growing season and are slightly more heat-tolerant than cantaloupe.

Whitman County, Washington is in USDA Zone 6a. The average last spring frost is May 10 and the first fall frost is September 29, giving you a growing season of approximately 142 days.

At an elevation of 1,541 feet, Whitman County receives approximately 14.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Honeydew during the growing season. With low rainfall, drip irrigation is essential for growing Honeydew successfully. Mulch heavily to conserve soil moisture.

Whitman County, WA (Zone 6a) Short season
142 days
Last Spring Frost May 10
142 growing days
First Fall Frost September 29

Whitman County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 20 🍅 Harvest: Aug 12 – Sep 23
Recommended (50%) ✗ May not fit
Transplant: May 31 🍅 Harvest: Aug 23 – Oct 4
Safe Start (90%) ✗ May not fit
Transplant: Jun 27 🍅 Harvest: Sep 19 – Oct 31

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
0.4″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 722 gal / 100 sq ft
Honeydew needs ~1,520 GDD — county provides 2,272 GDD Excellent fit

Honeydew Planting Timeline โ€” Whitman County, WA

Honeydew Planting Calendar

Activity When Date Range
Transplant Outdoors May 31 May 31 โ€“ Jun 14
Harvest August 23 Aug 23 โ€“ Oct 4

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

80โ€“110 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

142 days

Growing Tips for Whitman County

Start seeds indoors 4 weeks before transplanting. Plant on raised mounds of rich soil. Harvest when the blossom end gives slightly when pressed and the skin turns creamy yellow.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Honeydew in Whitman County, WA?

Whitman County is in Zone 6a with an average last frost of May 10. Plan your Honeydew planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Whitman County, WA?

Whitman County, Washington is in USDA Hardiness Zone 6a. The average last spring frost is May 10 and first fall frost is September 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Whitman 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 Whitman County, WA. Local conditions may vary. Last updated: April 2026.