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When to Plant Grapes in Florence County, WI

Florence County, Wisconsin Zone 4b May

May in the garden — Florence County, Wisconsin

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 26
Avg. first frost September 21
Soil temp (4") 56°F
Watering Low
Pest pressure Low
Daylight 14.7 hrs
June prep starts now
  • Transplants going out: grapes

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Grapes are vigorous climbing vines producing clusters of sweet or wine-quality fruits. They require training on a trellis or arbor and annual pruning for best production.

Florence County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 26 and the first fall frost is September 21, giving you a growing season of approximately 118 days.

At an elevation of 1,147 feet, Florence County receives approximately 34.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Grapes to ensure they mature before fall.

Florence County, WI (Zone 4b) Short season
118 days
Last Spring Frost May 26
118 growing days
First Fall Frost September 21
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Florence County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 17
Recommended (50%) ✓ Fits season
Transplant: Jun 23
Safe Start (90%) ✓ Fits season
Transplant: Jul 9

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 Florence County

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

Soil pH

Your soil pH (5.8–6.8) is within Grapes's preferred range (5.5–7.0).

Soil Texture

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

Organic Matter

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

How to Plant Grapes

72"
Between Plants
96"
Between Rows

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Grapes

Grapes needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Grapes Needs Rainfall You Supplement Action
Jan 1.2" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 3.4" 0" ❄️ Dormant
May 3" 4.4" 0" ✅ Rainfall sufficient
Jun 3" 4.4" 0" ✅ Rainfall sufficient
Jul 3" 3.2" 0" ✅ Rainfall sufficient
Aug 3" 4" 0" ✅ Rainfall sufficient
Sep 3" 2.9" 0.1" 💧 Light watering
Oct 2.7" 0" ❄️ Dormant
Nov 2.4" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Grapes 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.

Grapes needs ~10,494 GDD — county provides 1,357 GDD May not mature

Grapes Planting Timeline — Florence County, WI

Grapes Planting Calendar

Activity When Date Range
Transplant Outdoors June 23 Jun 23 – Jul 7

· 72" apart · Rows 96" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April
May
June Transplant Outdoors
July Transplant Outdoors
August
September
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 4b

📆 Growing Season

118 days in Florence County

Growing Tips for Grapes in Florence County

Direct sow Grapes outdoors after May 26 in Florence County when soil has warmed and frost danger has passed.

Your 118.0-day growing season in Florence County is tight for Grapes (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Provide a strong trellis system. Prune heavily in late winter while dormant. Thin fruit clusters for larger berries. Good air circulation prevents fungal diseases.

Companion Planting

Good Companions

Avoid Planting Near

  • Cabbage
  • Radish

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Grapes in Florence County, WI?

Florence County is in Zone 4b with an average last frost of May 26. Plan your Grapes planting based on this frost date — see the calendar above for exact timing.

What planting zone is Florence County, WI?

Florence County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 26 and first fall frost is September 21.

🌱

Your Florence County Garden Planner — Free

A 24-page printable planner built for Florence County (Zone 4b). 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 Florence 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.