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When to Plant Winter Melon in Lewis County, ID

Winter melon (wax gourd) is a large Asian squash with a waxy white coating that allows long storage. The mild flesh is used in soups and stir-fries.

Lewis County, Idaho is in USDA Zone 6a. The average last spring frost is May 20 and the first fall frost is September 23, giving you a growing season of approximately 126 days.

At an elevation of 4,861 feet, Lewis County receives approximately 13.5 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, providing good warmth for Winter Melon during the growing season. With low rainfall, drip irrigation is essential for growing Winter Melon successfully. Mulch heavily to conserve soil moisture.

Lewis County, ID (Zone 6a) Short season
126 days
Last Spring Frost May 20
126 growing days
First Fall Frost September 23

Lewis County Soil Profile

Soil Type

Loam

Soil pH

6.7-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Mar 17 Transplant: May 26 🍅 Harvest: Aug 25 – Oct 13
Recommended (50%) ✗ May not fit
Start indoors: Mar 25 Transplant: Jun 3 🍅 Harvest: Sep 2 – Oct 21
Safe Start (90%) ✗ May not fit
Start indoors: Apr 15 Transplant: Jun 24 🍅 Harvest: Sep 23 – Nov 11

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
0.7″/week
Watering frequency 1-2 times/week
Season total 740 gal / 100 sq ft
Drought risk

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

Winter Melon needs ~1,838 GDD — county provides 2,205 GDD Good fit

Winter Melon Planting Timeline โ€” Lewis County, ID

Winter Melon Planting Calendar

Activity When Date Range
Start Indoors March 25 Mar 25 โ€“ Apr 8
Transplant Outdoors June 3 Jun 3 โ€“ Jun 17
Direct Sow May 27 May 27 โ€“ Jun 17
Harvest September 2 Sep 2 โ€“ Oct 21

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

90โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6a

Growing Season

126 days

Growing Tips for Lewis County

Start seeds indoors 3-4 weeks early. Provide ample space for sprawling vines. Harvest when the waxy coating develops on the rind. Fruits can weigh 15-30 pounds.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Level Up Your Garden

Frequently Asked Questions

When should I plant Winter Melon in Lewis County, ID?

Lewis County is in Zone 6a with an average last frost of May 20. Plan your Winter Melon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lewis County, ID?

Lewis County, Idaho is in USDA Hardiness Zone 6a. The average last spring frost is May 20 and first fall frost is September 23.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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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 Lewis County, ID. Local conditions may vary. Last updated: April 2026.