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When to Plant Calabash in Grant County, WI

Grant County, Wisconsin Zone 5a May

Your May planting checklist for Grant County, Wisconsin

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

Avg. last frost April 28
Avg. first frost October 8
Soil temp (4") 54°F
Watering Low
Pest pressure Low
Daylight 14.5 hrs
  1. Move calabash into the garden

    Pick a cloudy afternoon or evening to plant. Less transplant shock, and your seedlings will barely blink.

  2. Plant calabash from seed, right in the garden

    Your soil is 54°F — warm enough for these to germinate without babying.

To set up a strong June, finish these tasks
  • Starting indoors: calabash

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Calabash (bottle gourd) is a tropical vine producing edible young fruits used in Asian and African cooking. Mature dried fruits serve as natural containers and utensils.

Grant County, Wisconsin is in USDA Zone 5a. The average last spring frost is April 28 and the first fall frost is October 8, giving you a growing season of approximately 163 days.

At an elevation of 884 feet, Grant County receives approximately 37.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Calabash to ensure they mature before fall.

Grant County, WI (Zone 5a) Moderate season
163 days
Last Spring Frost April 28
163 growing days
First Fall Frost October 8

Grant County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (9 days to spare)
Start indoors: Feb 26 Transplant: May 7 🍅 Harvest: Jul 30 – Sep 24
Recommended (50%) ✓ Fits season (9 days to spare)
Start indoors: Mar 3 Transplant: May 12 🍅 Harvest: Aug 4 – Sep 29
Safe Start (90%) ✓ Fits season (3 days to spare)
Start indoors: Mar 20 Transplant: May 29 🍅 Harvest: Aug 21 – Oct 16

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 Grant County

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

Soil pH

Your soil pH (6.1–7.1) is within Calabash's preferred range (6.0–7.5).

Soil Texture

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

Drainage

Drainage is adequate for Calabash.

Organic Matter

Organic matter is excellent (5.1%) — Calabash will thrive.

How to Plant Calabash

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

Succession Planting Calabash

2
successive plantings in your 163-day season

Sow every 9.1 weeks. Last sowing by Jun 10 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 469 gal / 100 sq ft

Monthly Watering Guide for Calabash

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

Month Calabash Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 5.2" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 4.4" 0" ✅ Rainfall sufficient
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 2.9" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Calabash 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.

Calabash needs ~1,075 GDD — county provides 1,752 GDD Excellent fit

Calabash Planting Timeline — Grant County, WI

Calabash Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors May 12 May 12 – May 26
Direct Sow May 5 May 5 – May 26
Harvest August 4 Aug 4 – Sep 29

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

Month-by-Month Timeline

MonthActivities
January
February
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

1"/week · 1-2 times/week

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7.5 · Your soil: ideal

🗺️ USDA Zone

Zone 5a

📆 Growing Season

163 days in Grant County

Growing Tips for Calabash in Grant County

Direct sow Calabash outdoors after April 28 in Grant County when soil has warmed and frost danger has passed.

Common pests for Calabash 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 4 weeks early. Provide a very strong trellis for heavy fruits. Harvest young for cooking or let mature on the vine for crafts. Requires a long, warm season.

Companion Planting

Good Companions

Avoid Planting Near

  • Potatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Calabash in Grant County, WI?

Grant County is in Zone 5a with an average last frost of April 28. Plan your Calabash planting based on this frost date — see the calendar above for exact timing.

What planting zone is Grant County, WI?

Grant County, Wisconsin is in USDA Hardiness Zone 5a. The average last spring frost is April 28 and first fall frost is October 8.

🌱

Your Grant County Garden Planner — Free

A 24-page printable planner built for Grant County (Zone 5a). 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 Grant County, WI. 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.