Blog

When to Plant Cranberries in Richland County, IL

Richland County, Illinois Zone 6b May

Your May gardening checklist

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 April 13
Avg. first frost October 27
Soil temp (4") 61°F
Watering Low
Pest pressure Low
Daylight 14.1 hrs
  1. Plant out cranberries

    Bring a watering can to the bed. Each transplant gets a drink the moment it's in the ground, not ten minutes later.

Instant PDF download. No spam, unsubscribe any time.

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.

Richland County, Illinois is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 27, giving you a growing season of approximately 197 days.

At an elevation of 1,135 feet, Richland County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Cranberries during the growing season.

Richland County, IL (Zone 6b) Moderate season
197 days
Last Spring Frost April 13
197 growing days
First Fall Frost October 27

Richland County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 28
Recommended (50%) ✓ Fits season
Transplant: May 4
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 Richland County

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

Soil pH

Your soil pH (6.2–7.0) is more alkaline than Cranberries prefers (4.0–5.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.0%) — Cranberries will thrive.

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
0.7″/week
Watering frequency 1-2 times/week
Season total 1,146 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 1.7" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 6.5" 4.3" 2.2" 💧 Light watering
May 6.5" 4" 2.5" 💧 Light watering
Jun 6.5" 4.5" 2" 💧 Light watering
Jul 6.5" 4.4" 2.1" 💧 Light watering
Aug 6.5" 4.4" 2.1" 💧 Light watering
Sep 6.5" 3.8" 2.7" 💧 Light watering
Oct 6.5" 3" 3.5" 🚿 Regular watering
Nov 3" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Richland County). Supplement amounts are based on average rainfall — 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" — 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.

Cranberries needs ~16,653 GDD — county provides 3,595 GDD May not mature

Cranberries Planting Timeline — Richland County, IL

Cranberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 4 May 4 – May 18

· 36" apart · Rows 48" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.5"/week · 1-2 times/week

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 4–5.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6b

📆 Growing Season

197 days in Richland County

Growing Tips for Cranberries in Richland County

Direct sow Cranberries outdoors after April 13 in Richland County when soil has warmed and frost danger has passed.

Your 197.0-day growing season in Richland 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 Richland County, IL?

Richland County is in Zone 6b with an average last frost of April 13. Plan your Cranberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Richland County, IL?

Richland County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 27.

🌱

Your Richland County Garden Planner — Free

A 24-page printable planner built for Richland County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Richland County, IL. 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.