When to Plant Watermelon in Smith County, KS
May in the garden — Smith County, Kansas
Your Smith County, Kansas garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Move watermelon from tray to bed
Harden off for 7 days — a little more sun each day — before planting. That's the difference between a seedling that thrives and one that stalls.
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Begin indoor sowing: watermelon
You're about 20 weeks out from your last frost — the perfect window to get these germinating indoors.
Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.
Smith County, Kansas is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 14, giving you a growing season of approximately 174 days.
At an elevation of 1,048 feet, Smith County receives approximately 26.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Watermelon to ensure they mature before fall.
Smith County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.3
Drainage
Well Drained
Plant Planting Risk Windows
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 Smith County
How your county's soil matches Watermelon's growing requirements.
Soil pH
Your soil pH (6.5–7.3) is within Watermelon's preferred range (6.0–7.5).
Soil Texture
The loam soil in Smith County is excellent for Watermelon — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Watermelon.
Organic Matter
Organic matter is moderate (3.4%). Annual compost additions will help Watermelon.
How to Plant Watermelon
Succession Planting Watermelon
Sow every 8 weeks. Last sowing by Jul 06 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Watermelon
Watermelon needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Watermelon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.7" | 0" | ❄️ Dormant |
| Apr | 6.5" | 2.6" | 3.9" | 🚿 Regular watering |
| May | 6.5" | 3.7" | 2.8" | 💧 Light watering |
| Jun | 6.5" | 4.1" | 2.4" | 💧 Light watering |
| Jul | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| Aug | 6.5" | 3.4" | 3.1" | 💧 Light watering |
| Sep | 6.5" | 2.3" | 4.2" | 🚿 Regular watering |
| Oct | 6.5" | 1.9" | 4.6" | 🚿 Regular watering |
| Nov | — | 1" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Smith County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Watermelon 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.
Watermelon Planting Timeline — Smith County, KS
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 19 | Mar 19 – Apr 2 |
| Transplant Outdoors | May 7 | May 7 – May 21 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Harvest | July 16 | Jul 16 – Sep 3 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 2-3 times/week
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 6a
📆 Growing Season
174 days in Smith County
Growing Tips for Watermelon in Smith County
Direct sow Watermelon outdoors after April 23 in Smith County when soil has warmed and frost danger has passed.
Common pests for Watermelon in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Watermelon in Other Locations
Frequently Asked Questions
When should I plant Watermelon in Smith County, KS?
Smith County is in Zone 6a with an average last frost of April 23. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Smith County, KS?
Smith County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 14.
Your Smith County Garden Planner — Free
A 24-page printable planner built for Smith County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.