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 7a. 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 Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.2
Drainage
Well Drained
Plant Planting Risk Windows
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.
Plant Water Budget
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
| Month | Activities |
|---|---|
| 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
6 – 7.5
USDA Zone
Zone 7a
Growing Season
191 days
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
Level Up Your Garden
Cardoon in Other Locations
Frequently Asked Questions
When should I plant Cardoon in Delaware County, PA?
Delaware County is in Zone 7a 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 7a. The average last spring frost is April 16 and first fall frost is October 24.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Delaware County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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