How to Grow Cardoon: Planting, Spacing, Care & Harvest

Quick answer

Start indoors 6–8 weeks before last frost (WI). Transplant after frost danger (WI). NC State: weedy in some areas; invasive colonies reported in places such as California.

Cardoon at a glance

PlantStart indoors: 8–6 wk before last frost; Transplant: last frost
SunNC: rich, well-drained but moist soil and full sun.
SpacingWI: under ideal conditions plants can reach 3 to 4 feet tall and 4 to 5 feet wide by season’s end — give them room.
Days to harvestAbout 110 days from transplant for one variety, 'Bianco Avorio' (Wisconsin)
-9-8-7-6-5-4-3-2-1LF+1+2+3
■ Start indoors   ■ Plant out   ■ Harvest
Weeks relative to last frost (LF). Colored weeks show when our ZIP planner schedules each step.
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Updated

Planting dates for your ZIP: the ZIP planting planner counts each window from your local frost dates.

Organic pests and diseases: see also organic pest control. Use any product as the label directs.

Not globe artichoke: cardoon is Cynara cardunculus grown for leaf stalks (and ornament); globe artichoke is a different crop. See globe artichoke.

Weedy / invasive: NC State: “Considered weedy in some areas.” “In some locations, such as California, it has spread to form colonies, and is considered to be invasive.” Remove the large taproot to prevent resprouting. (NC State Cynara cardunculus)

Cardoon flower bud
Cardoon (Cynara cardunculus). Photo: Jim Evans, Wikimedia Commons, CC BY-SA 4.0 (resized).

Planting timing

Wisconsin Horticulture: “Cardoon can be started from seed sown indoors 6 to 8 weeks before the last frost. Transplant to the garden after the danger of frost is past.” (Wisconsin cardoon)

Depth and spacing

WI: under ideal conditions plants can reach 3 to 4 feet tall and 4 to 5 feet wide by season’s end — give them room. Full sun, well-drained soil, shelter from strong wind.

Sun, soil and water

NC: rich, well-drained but moist soil and full sun. May go dormant in hot summers; dies back in winter. Mulch heavily where overwintering is attempted.

Care

WI: trim older flopping leaves to keep a vase shape. Cold-climate overwintering is uncertain — WI describes cutting back and insulating; success is not guaranteed.

Harvest

Blanch leaf stalks before harvest for milder flavor where grown as a vegetable (cultural practice on many extension pages). Ornamental thistle buds are a secondary use.

Pests and diseases

WI: few pests when grown as an annual; Japanese beetle reported in the East. Deer usually leave it alone.

Related: globe artichoke · ZIP planner · organic pest control

Frequently asked questions

When do I start cardoon?

Indoors 6–8 weeks before last frost; transplant after frost (WI).

Is it invasive?

NC State: weedy in some areas; invasive colonies reported in places such as California — remove the taproot.

Same as artichoke?

Related Cynara, different crop — see globe artichoke.

More grow guides: All grow guides

Sources