When to Plant Zucchini in Harrison County, IN
Zucchini is an incredibly prolific summer squash that can produce an abundance of fruit from just a few plants. It is versatile in the kitchen from grilling to baking.
Harrison County, Indiana is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 31, giving you a growing season of approximately 206 days.
At an elevation of 528 feet, Harrison County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Zucchini during the growing season.
Harrison County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-7.1
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 Harrison County
How your county's soil matches Zucchini's growing requirements.
Soil pH
Your soil pH (5.7–7.1) overlaps with Zucchini's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Harrison County is excellent for Zucchini — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.2%) — Zucchini will thrive.
How to Plant Zucchini
Succession Planting Zucchini
Sow every 5.1 weeks. Last sowing by Sep 01 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Zucchini
Zucchini needs approximately 1.2 inches of water per week (5.2" per month). Here's how your county's rainfall compares month by month.
| Month | Zucchini Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 3" | 0" | ❄️ Dormant |
| Apr | 5.2" | 4.1" | 1.1" | 💧 Light watering |
| May | 5.2" | 4.8" | 0.4" | 💧 Light watering |
| Jun | 5.2" | 5.4" | 0" | ✅ Rainfall sufficient |
| Jul | 5.2" | 4.6" | 0.6" | 💧 Light watering |
| Aug | 5.2" | 4.7" | 0.5" | 💧 Light watering |
| Sep | 5.2" | 3.2" | 2" | 💧 Light watering |
| Oct | 5.2" | 3" | 2.2" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Harrison County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Zucchini 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.
Zucchini Planting Timeline — Harrison County, IN
Zucchini Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 4 | Mar 4 – Mar 18 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 15 | Apr 15 – May 6 |
| Harvest | June 10 | Jun 10 – Aug 5 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.2"/week · 1-2 times/week
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
206 days in Harrison County
Growing Tips for Zucchini in Harrison County
Direct sow Zucchini outdoors after April 08 in Harrison County when soil has warmed and frost danger has passed.
Your generous 206.0-day season in Harrison County allows multiple plantings of Zucchini. Sow every 22.0 days for continuous harvest.
Common pests for Zucchini in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow after last frost. Harvest when fruits are 6-8 inches long for best flavor and texture. Check plants daily in summer as fruits can double in size overnight.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Zucchini in Other Locations
Frequently Asked Questions
When should I plant Zucchini in Harrison County, IN?
Harrison County is in Zone 6b with an average last frost of April 8. Plan your Zucchini planting based on this frost date — see the calendar above for exact timing.
What planting zone is Harrison County, IN?
Harrison County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 31.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Harrison County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.
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