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When to Plant Cardoon in Delaware County, PA

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.

Delaware County, Pennsylvania is in USDA Zone 7b. The average last spring frost is April 16 and the first fall frost is October 24, giving you a growing season of approximately 191 days.

At an elevation of 1,094 feet, Delaware County receives approximately 38.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Cardoon during the growing season.

Delaware County, PA (Zone 7b) Moderate season
191 days
Last Spring Frost April 16
191 growing days
First Fall Frost October 24

Delaware County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.2

Drainage

Well Drained

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 2.9" 0" ❄️ Dormant
Feb 2.3" 0" ❄️ Dormant
Mar 3.1" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 3.2" 1.1" 💧 Light watering
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 3.7" 0.6" 💧 Light watering
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

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

Cardoon Planting Timeline — Delaware County, PA

Cardoon Planting Calendar

Activity When Date Range
Transplant Outdoors April 30 Apr 30 – May 14
Harvest September 3 Sep 3 – Oct 15

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

120–150 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 7b

📆 Growing Season

191 days in Delaware County

Growing Tips for Delaware County

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 Delaware County, PA?

Delaware County is in Zone 7b with an average last frost of April 16. Plan your Cardoon planting based on this frost date — see the calendar above for exact timing.

What planting zone is Delaware County, PA?

Delaware County, Pennsylvania is in USDA Hardiness Zone 7b. The average last spring frost is April 16 and first fall frost is October 24.

🌱

Your Delaware County Garden Planner — Free

A 22-page printable planner built for Delaware County (Zone 7b). 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 Delaware County, PA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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