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When to Plant Cranberries in Franklin County, KY

Cranberries are low-growing, vine-like shrubs that produce tart red berries in fall. They grow in acidic, boggy conditions and are surprisingly easy to cultivate.

Franklin County, Kentucky is in USDA Zone 6b. The average last spring frost is April 11 and the first fall frost is October 26, giving you a growing season of approximately 198 days.

At an elevation of 3,532 feet, Franklin County receives approximately 44.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Cranberries during the growing season.

Franklin County, KY (Zone 6b) Moderate season
198 days
Last Spring Frost April 11
198 growing days
First Fall Frost October 26

Franklin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.6-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 28
Recommended (50%) ✓ Fits season
Transplant: May 2
Safe Start (90%) ✓ Fits season
Transplant: May 18

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 Franklin County

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

Soil pH

Your soil pH (5.6โ€“7.0) is more alkaline than Cranberries prefers (4.0โ€“5.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Cranberries.

How to Plant Cranberries

36"
Between Plants
48"
Between Rows

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.9″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 987 gal / 100 sq ft

Monthly Watering Guide for Cranberries

Cranberries needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.

Month Cranberries Needs Rainfall You Supplement Action
Jan โ€” 3.8" 0" โ„๏ธ Dormant
Feb โ€” 3" 0" โ„๏ธ Dormant
Mar โ€” 4.7" 0" โ„๏ธ Dormant
Apr 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
May 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Jun 6.5" 3.4" 3.1" ๐Ÿ’ง Light watering
Jul 6.5" 4.7" 1.8" ๐Ÿ’ง Light watering
Aug 6.5" 4.3" 2.2" ๐Ÿ’ง Light watering
Sep 6.5" 3.5" 3" ๐Ÿ’ง Light watering
Oct 6.5" 3.1" 3.4" ๐Ÿšฟ Regular watering
Nov โ€” 3.7" 0" โ„๏ธ Dormant
Dec โ€” 3.2" 0" โ„๏ธ Dormant

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

Cranberries 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.

Cranberries needs ~14,600 GDD — county provides 3,168 GDD May not mature

Cranberries Planting Timeline โ€” Franklin County, KY

Cranberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 2 May 2 โ€“ May 16

ยท 36" apart ยท Rows 48" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.5"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

730โ€“1095 days

๐Ÿงช Soil pH

Needs 4โ€“5.5 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

198 days in Franklin County

Growing Tips for Cranberries in Franklin County

Direct sow Cranberries outdoors after April 11 in Franklin County when soil has warmed and frost danger has passed.

Your 198.0-day growing season in Franklin County is tight for Cranberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.

General growing tips

Create an acidic, consistently moist bed with peat moss. Cranberries do not need to be flooded to grow; flooding is only used for commercial harvesting. Mulch with sand in early spring.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cranberries in Franklin County, KY?

Franklin County is in Zone 6b with an average last frost of April 11. Plan your Cranberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Franklin County, KY?

Franklin County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 11 and first fall frost is October 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Franklin County gardeners in Zone 6b 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 Franklin County, KY. Local conditions may vary. Last updated: April 2026.