Cardoon Seeds - Large Smooth

Minimum Seeds per Packet: 17

Packet Weight: 1g

Planting Season: Spring

Sowing Method: Transplant

Seed Depth: 1/2"

Direct Seed Spacing: N/A

Soil Temperature: 55-80 ℉

Days to Sprout: 7-14

Mature Spacing: 4'

Sun Requirement: Full Sun

Frost Tolerance: Frost Sensitive

Days to Harvest: 115

When to Seed Cardoon

Start seeds indoors eight to ten weeks before your last frost. Be sure to keep the seed tray warm and ensure it receives plenty of light. They can be transplanted outdoors after all danger of frost has passed and the soil is warmed (about two weeks after your last frost date). 

Where to Plant Cardoon

Choose a spot with full sun and rich, well-draining soil with a pH between six and seven. Cardoon can be grown as a perennial in zones seven through ten, and even growers in colder climates may be able to overwinter their cardoons with enough mulch. With this in mind, if you plan to grow cardoons perennially, pick a spot they can stay for a while! 

Growing Cardoon

Cardoon seeds should be planted ½ inch deep, and transplanted into the garden four feet apart. While cardoon is typically a low maintenance plant, it will require at least an inch of water per week. In late summer, once you have plenty of thick stalks, the real work begins. Blanching your cardoon stems keeps them tender for your harvest. Gather the stems together and wrap them in something that will keep light out. Cardboard, several layers of newspaper, or a dark colored fabric or towel will all work. Tie the bundle together with twine allowing the upper leaves to stick out at the top. Leave your plants this way for three to four weeks. When you remove the wrapping, the stems will be pale colored and more tender than they would be without blanching. 

Harvesting Cardoon

Harvest cardoon by cutting all the blanched stems off at the base of the plant, then trim the leaves. Cardoon can be used like celery in soups or even sauteed.

Cardoon (Cynara carbunculus) is an insect-pollinated perennial that typically flowers starting in its second year. It needs to be isolated from other varieties of cardoon or artichokes by at least 800 feet to prevent cross-pollination. In some areas of California and the Southwest, there may be naturalized cardoon or artichoke in the environment, so pay attention to what’s blooming in the wild near your garden.

In about 60 days after cardoon’s large, thistle-like flowers are pollinated, the bracts (spiky parts surrounding the flower) will begin to turn brown and silvery-gray pappi (fluffy projections like the ones on dandelion seeds) will begin to emerge from the top of the flower. At this point, the flowers can be cut off and brought inside to finish drying. When the flowers are entirely crunchy and brown, break them open (wear gloves, they’re spiky!), pull the seeds out and separate each one from its pappus. Store the seeds in an airtight container in a dark, dry, and cool location.