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When to Plant Potatoes in Delaware County, IN

Potatoes are a versatile staple crop that produces tubers underground. They come in hundreds of varieties with varying colors, textures, and maturity dates.

Delaware County, Indiana is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 16, giving you a growing season of approximately 173 days.

At an elevation of 739 feet, Delaware County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Potatoes to ensure they mature before fall.

Delaware County, IN (Zone 5b) Moderate season
173 days
Last Spring Frost April 26
173 growing days
First Fall Frost October 16

Delaware County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Feb 25 Transplant: May 6 🍅 Harvest: Jul 15 – Sep 23
Recommended (50%) ✓ Fits season (19 days to spare)
Start indoors: Mar 1 Transplant: May 10 🍅 Harvest: Jul 19 – Sep 27
Safe Start (90%) ✓ Fits season (13 days to spare)
Start indoors: Mar 17 Transplant: May 26 🍅 Harvest: Aug 4 – Oct 13

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 Delaware County

How your county's soil matches Potatoes's growing requirements.

Soil pH

Your soil pH (6.0โ€“7.0) overlaps with Potatoes's range (5.0โ€“6.5), though not a perfect match.

Soil Texture

The silt loam soil in Delaware County is excellent for Potatoes โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.8%) โ€” Potatoes will thrive.

How to Plant Potatoes

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Potatoes

2
successive plantings in your 173-day season

Sow every 8 weeks. Last sowing by Jun 18 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 377 gal / 100 sq ft

Monthly Watering Guide for Potatoes

Potatoes needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Potatoes Needs Rainfall You Supplement Action
Jan โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2" 0" โ„๏ธ Dormant
Apr 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
May 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Jun 4.3" 3.7" 0.6" ๐Ÿ’ง Light watering
Jul 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Aug 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Sep 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
Oct 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Nov โ€” 2.4" 0" โ„๏ธ Dormant
Dec โ€” 1.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Delaware County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Potatoes 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" โ€” every day above 50ยฐF 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.

Potatoes needs ~1,164 GDD — county provides 2,119 GDD Excellent fit

Potatoes Planting Timeline โ€” Delaware County, IN

Potatoes Planting Calendar

Activity When Date Range
Start Indoors March 1 Mar 1 โ€“ Mar 15
Transplant Outdoors May 10 May 10 โ€“ May 24
Direct Sow May 3 May 3 โ€“ May 24
Harvest July 19 Jul 19 โ€“ Sep 27

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

70โ€“120 days

๐Ÿงช Soil pH

Needs 5โ€“6.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

173 days in Delaware County

Growing Tips for Potatoes in Delaware County

Direct sow Potatoes outdoors after April 26 in Delaware County when soil has warmed and frost danger has passed.

Common pests for Potatoes in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant seed potatoes (not grocery store potatoes) 4 inches deep in spring. Hill soil around stems as plants grow to prevent greening. Stop watering when plants die back.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Cucumber
  • Squash Summer

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Potatoes in Delaware County, IN?

Delaware County is in Zone 5b with an average last frost of April 26. Plan your Potatoes planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Delaware County, IN?

Delaware County, Indiana is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Delaware County gardeners in Zone 5b 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 Delaware County, IN. Local conditions may vary. Last updated: April 2026.