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When to Plant Cardoon in Caroline County, MD

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.

Caroline County, Maryland is in USDA Zone 7a. The average last spring frost is April 4 and the first fall frost is November 4, giving you a growing season of approximately 214 days.

At an elevation of 469 feet, Caroline County receives approximately 40.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88ยฐF, providing good warmth for Cardoon during the growing season.

Caroline County, MD (Zone 7a) Long season
214 days
Last Spring Frost April 4
214 growing days
First Fall Frost November 4

Caroline County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (33 days to spare)
Transplant: Apr 12 🍅 Harvest: Aug 16 – Sep 27
Recommended (50%) ✓ Fits season (32 days to spare)
Transplant: Apr 18 🍅 Harvest: Aug 22 – Oct 3
Safe Start (90%) ✓ Fits season (26 days to spare)
Transplant: May 6 🍅 Harvest: Sep 9 – Oct 21

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 Caroline County

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

Soil pH

Your soil pH (5.3โ€“6.8) overlaps with Cardoon's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Caroline County is excellent for Cardoon โ€” good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Cardoon.

Organic Matter

Organic matter is moderate (3.2%). 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
0.8″/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 โ€” 2.6" 0" โ„๏ธ Dormant
Feb โ€” 2.4" 0" โ„๏ธ Dormant
Mar โ€” 3.3" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Aug 4.3" 3.5" 0.8" ๐Ÿ’ง Light watering
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Nov 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Dec โ€” 2.7" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Caroline County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~2,160 GDD — county provides 3,424 GDD Excellent fit

Cardoon Planting Timeline โ€” Caroline County, MD

Cardoon Planting Calendar

Activity When Date Range
Transplant Outdoors April 18 Apr 18 โ€“ May 2
Harvest August 22 Aug 22 โ€“ Oct 3

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

120โ€“150 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

214 days in Caroline County

Growing Tips for Cardoon in Caroline County

Direct sow Cardoon outdoors after April 04 in Caroline County when soil has warmed and frost danger has passed.

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 Caroline County, MD?

Caroline County is in Zone 7a with an average last frost of April 4. Plan your Cardoon planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Caroline County, MD?

Caroline County, Maryland is in USDA Hardiness Zone 7a. The average last spring frost is April 4 and first fall frost is November 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Caroline County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Caroline County, MD. Local conditions may vary. Last updated: April 2026.