When to Plant Winter Melon in Johnson County, IA
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.
Johnson County, Iowa is in USDA Zone 5a. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.
At an elevation of 1,204 feet, Johnson County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Winter Melon during the growing season.
Johnson County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.3
Drainage
Well Drained
Monthly Watering Guide for Winter Melon
Winter Melon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Winter Melon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2" | 0" | ❄️ Dormant |
| Mar | — | 2.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Sep | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 2.9" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Johnson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Winter Melon Planting Timeline — Johnson County, IA
Winter Melon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 27 | Feb 27 – Mar 13 |
| Transplant Outdoors | May 8 | May 8 – May 22 |
| Direct Sow | May 1 | May 1 – May 22 |
| Harvest | August 7 | Aug 7 – Sep 25 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | — |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 5a
📆 Growing Season
170 days in Johnson County
Growing Tips for Johnson 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
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Winter Melon in Other Locations
Frequently Asked Questions
When should I plant Winter Melon in Johnson County, IA?
Johnson County is in Zone 5a with an average last frost of April 24. Plan your Winter Melon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Johnson County, IA?
Johnson County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 24 and first fall frost is October 11.
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