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When to Plant Cardoon in Clayton County, GA

Clayton County, Georgia Zone 8b May

This month in Clayton County, Georgia

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 March 28
Avg. first frost November 3
Soil temp (4") 70°F
Watering Low
Pest pressure Moderate
Daylight 13.7 hrs

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Cardoon is a large thistle relative of the artichoke, grown for its edible leaf stalks. It has dramatic silvery foliage and makes a striking ornamental as well.

Clayton County, Georgia is in USDA Zone 8b. The average last spring frost is March 28 and the first fall frost is November 3, giving you a growing season of approximately 220 days.

At an elevation of 136 feet, Clayton County receives approximately 56.2 inches of rainfall annually with predominantly clay loam soil. Summer highs average 92°F, providing good warmth for Cardoon during the growing season. Clay soil retains moisture well for Cardoon, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cardoon root diseases.

Clayton County, GA (Zone 8b) Long season
220 days
Last Spring Frost March 28
220 growing days
First Fall Frost November 3

Clayton County Soil Profile

Soil Type

Clay Loam

Soil pH

5.6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (39 days to spare)
Transplant: Apr 5 🍅 Harvest: Aug 9 – Sep 20
Recommended (50%) ✓ Fits season (38 days to spare)
Transplant: Apr 11 🍅 Harvest: Aug 15 – Sep 26
Safe Start (90%) ✓ Fits season (33 days to spare)
Transplant: May 2 🍅 Harvest: Sep 5 – Oct 17

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 Clayton County

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

Soil pH

Your soil pH (5.6–6.8) overlaps with Cardoon's range (6.0–7.5), though not a perfect match.

Soil Texture

The clay loam soil in Clayton County is excellent for Cardoon — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

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

How to Plant Cardoon

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

Plant Water Budget

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

Monthly Watering Guide for Cardoon

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

Month Cardoon Needs Rainfall You Supplement Action
Jan 5" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 4.3" 5.1" 0" ✅ Rainfall sufficient
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 5.1" 0" ✅ Rainfall sufficient
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 6.3" 0" ✅ Rainfall sufficient
Aug 4.3" 5.6" 0" ✅ Rainfall sufficient
Sep 4.3" 4.1" 0.2" 💧 Light watering
Oct 4.3" 4.1" 0.2" 💧 Light watering
Nov 4.3" 3.7" 0.6" 💧 Light watering
Dec 4.1" 0" ❄️ Dormant

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

Cardoon 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.

Cardoon needs ~2,565 GDD — county provides 4,180 GDD Excellent fit

Cardoon Planting Timeline — Clayton County, GA

Cardoon Planting Calendar

Activity When Date Range
Transplant Outdoors April 11 Apr 11 – Apr 25
Harvest August 15 Aug 15 – Sep 26

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

120–150 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

220 days in Clayton County

Growing Tips for Cardoon in Clayton County

Direct sow Cardoon outdoors after March 28 in Clayton County when soil has warmed and frost danger has passed.

With Clayton County's clay soil (30% clay), work in 3-4 inches of compost before planting Cardoon. Avoid tilling when soil is wet to prevent compaction.

Common pests for Cardoon in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Blanch stalks by wrapping with cardboard or tying leaves together 3-4 weeks before harvest. Provide deep, rich soil and consistent moisture. Protect from hard frost.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cardoon in Clayton County, GA?

Clayton County is in Zone 8b with an average last frost of March 28. Plan your Cardoon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clayton County, GA?

Clayton County, Georgia is in USDA Hardiness Zone 8b. The average last spring frost is March 28 and first fall frost is November 3.

🌱

Your Clayton County Garden Planner — Free

A 24-page printable planner built for Clayton County (Zone 8b). 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 Clayton County, GA. 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.