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When to Plant Delicata Squash in Cass County, IA

Cass County, Iowa Zone 5b May

Your May planting checklist for Cass County, Iowa

Each item below is timed to Cass County, Iowa's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 25
Avg. first frost October 9
Soil temp (4") 57°F
Watering Moderate
Pest pressure Low
Daylight 14.3 hrs
  1. Harden off and plant delicata squash

    Pinch off the lowest leaves on each seedling before you plant — it reduces water loss while the roots catch up.

  2. Put delicata squash seeds straight in the ground

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

  3. Get delicata squash seeds going inside

    Label every cell. You will absolutely forget which is which otherwise.

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Delicata squash is a winter squash with an edible skin and sweet, creamy orange flesh. Its compact vines make it suitable for smaller gardens.

Cass County, Iowa is in USDA Zone 5b. The average last spring frost is April 25 and the first fall frost is October 9, giving you a growing season of approximately 167 days.

At an elevation of 1,043 feet, Cass County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Delicata Squash during the growing season.

Cass County, IA (Zone 5b) Moderate season
167 days
Last Spring Frost April 25
167 growing days
First Fall Frost October 9

Cass County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Mar 16 Transplant: May 4 🍅 Harvest: Jul 27 – Aug 31
Recommended (50%) ✓ Fits season (34 days to spare)
Start indoors: Mar 21 Transplant: May 9 🍅 Harvest: Aug 1 – Sep 5
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Apr 7 Transplant: May 26 🍅 Harvest: Aug 18 – Sep 22

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 Cass County

How your county's soil matches Delicata Squash's growing requirements.

Soil pH

Your soil pH (6.2–6.7) is within Delicata Squash's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Cass County is excellent for Delicata Squash — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.4%) — Delicata Squash will thrive.

How to Plant Delicata Squash

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Succession Planting Delicata Squash

2
successive plantings in your 167-day season

Sow every 9.1 weeks. Last sowing by Jul 01 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 324 gal / 100 sq ft

Monthly Watering Guide for Delicata Squash

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

Month Delicata Squash Needs Rainfall You Supplement Action
Jan 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 4.3" 2.9" 1.4" 💧 Light watering
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 3.7" 0.6" 💧 Light watering
Jul 4.3" 3.4" 0.9" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.9" 1.4" 💧 Light watering
Oct 4.3" 2.4" 1.9" 💧 Light watering
Nov 2.1" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Delicata Squash 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.

Delicata Squash needs ~1,305 GDD — county provides 2,421 GDD Excellent fit

Delicata Squash Planting Timeline — Cass County, IA

Delicata Squash Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 9 May 9 – May 23
Direct Sow May 2 May 2 – May 23
Harvest August 1 Aug 1 – Sep 5

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

80–100 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

167 days in Cass County

Growing Tips for Delicata Squash in Cass County

Direct sow Delicata Squash outdoors after April 25 in Cass County when soil has warmed and frost danger has passed.

Common pests for Delicata Squash 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 on mounds. Harvest when skin is hard and ivory with green stripes. The thin skin does not need peeling. Stores 2-3 months in a cool place.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Delicata Squash in Cass County, IA?

Cass County is in Zone 5b with an average last frost of April 25. Plan your Delicata Squash planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cass County, IA?

Cass County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 25 and first fall frost is October 9.

🌱

Your Cass County Garden Planner — Free

A 24-page printable planner built for Cass County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Cass County, IA. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.