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When to plant Cranberries in Whiteside County, IL

In Whiteside County, Cranberries is a single-season spring crop — there's no second fall window. Plant May 7–May 21 for an 730–1095-day harvest, finishing well before the October 16 first frost.

When to Plant Cranberries in Whiteside County, IL

Whiteside County, Illinois Zone 5b July

Your July planting checklist for Whiteside County, Illinois

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

Avg. last frost April 16
Avg. first frost October 16
Soil temp (4") 77°F
Watering Moderate
Pest pressure High
Daylight 14.7 hrs

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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.

Whiteside County, Illinois is in USDA Zone 5b. The average last spring frost is April 16 and the first fall frost is October 16, giving you a growing season of approximately 183 days.

At an elevation of 682 feet, Whiteside County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Cranberries to ensure they mature before fall.

Whiteside County, IL (Zone 5b) Moderate season
183 days
Last Spring Frost April 16
183 growing days
First Fall Frost October 16

Whiteside County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Cranberries Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 1
Recommended (50%) ✓ Fits season
Transplant: May 7
Safe Start (90%) ✓ Fits season
Transplant: May 23

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 Whiteside County

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

Soil pH

Your soil pH (5.9–6.7) 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 Whiteside County is excellent for Cranberries — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Cranberries.

How to Plant Cranberries

36"
Between Plants
48"
Between Rows

Cranberries Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,314 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 1.2" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 6.5" 3.3" 3.2" 💧 Light watering
May 6.5" 3.1" 3.4" 🚿 Regular watering
Jun 6.5" 3.7" 2.8" 💧 Light watering
Jul 6.5" 3.4" 3.1" 💧 Light watering
Aug 6.5" 3.3" 3.2" 💧 Light watering
Sep 6.5" 2.8" 3.7" 🚿 Regular watering
Oct 6.5" 2.3" 4.2" 🚿 Regular watering
Nov 2.1" 0" ❄️ Dormant
Dec 1.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Whiteside 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 ~11,862 GDD — county provides 2,379 GDD May not mature

Cranberries Planting Timeline — Whiteside County, IL

Cranberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 7 May 7 – May 21

· 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 · 2-3 times/week

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 4–5.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 5b

📆 Growing Season

183 days in Whiteside County

Growing Tips for Cranberries in Whiteside County

Direct sow Cranberries outdoors after April 16 in Whiteside County when soil has warmed and frost danger has passed.

Your 183.0-day growing season in Whiteside 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 Whiteside County, IL?

Whiteside County is in Zone 5b with an average last frost of April 16. Plan your Cranberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Whiteside County, IL?

Whiteside County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 16 and first fall frost is October 16.

When should I plant Cranberries in Whiteside County, IL?

In Whiteside County, IL, plant Cranberries after the last frost (around April 16) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Whiteside County, IL for Cranberries?

Whiteside County sits in USDA Zone 5b. Cranberries grows reliably in zones 2a through 7b, so it's a good fit here.

Can Cranberries grow in Whiteside County's climate?

Yes — Cranberries grows well in Whiteside County's temperate climate. Whiteside County averages a 183-day frost-free season, with last frost around April 16 and first frost around October 16.

🌱

Your Whiteside County Garden Planner — Free

A 22-page printable planner built for Whiteside 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 Whiteside County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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