If you’re looking for a bold, edible plant to include in your farm’s garden, look no further than the cardoon (Cynara cardunculus). Though growing cardoons is easy and the plants are super-cool looking, harvesting and eating them isn’t exactly a walk in the park. The plant is covered with spines, but the effort is worth it because the flavor is surprisingly divine.
What Is A Cardoon?
Cardoon is a wild cousin to the artichoke, but unlike artichokes, the edible portion is not the flower bud. Instead cardoon-lovers primarily eat the blanched leaf stalks (though the buds are edible, too).
Cardoons are gorgeous plants. In climates with cold winters, like my Pennsylvania garden, a full-size cardoon will reach about three or four feet in height with an equal spread, but in warmer climes, its stature is even more massive—cardoons will grow up to five feet high and wide. A very striking plant indeed!
The heavily serrated leaves are coated with silvery fuzz and peppered with prickly spines, making the plants a real standout in the garden. They look a lot like enormous purple thistles when they come into flower (which may not happen in northern climates like mine), and the bees and butterflies really enjoy the blooms, too.
The Ins & Outs Of Growing Cardoons
To begin your foray into growing cardoons, it’s important to select the right variety.
If you’re worried about battling the spines, look for a spineless variety such as Gigante or Porto Spineless. Other tasty varieties include Gobbo Di Nizzia and Rouge d’Alger.
Cardoons require a very long growing season of at least 90 to 100 days, if not more. To give them a head start, sow the seeds indoors under grow lights in the late winter, potting the seedlings up once or twice as they grow. Cardoon seedlings can be transplanted outdoors after the danger of frost has passed, around the same time your tomatoes and basil go out into the garden.
Cardoon plants get huge, so needless to say, give them plenty of space. Ideally, they should be spaced about five to six feet apart on center. They are gorgeous plants and because of this, many gardeners may choose to grow this edible in their ornamental beds, mixing it with colorful flowers and foliage plants to really let it shine.
Allow the plants to grow throughout the summer months, feeding them every other week with an organic liquid fertilizer, such as fish emulsion, compost tea or liquid kelp. You’ll also need to make sure they receive ample moisture. These big plants are fairly drought resistant, but to grow the biggest, juiciest stems for harvest, make sure the receive at least an inch of water per week.
In late summer/early fall, it’s time to blanch your cardoon to improve the flavor and soften the texture of the stems.
How To Blanch Cardoons
Cardoon blanching takes three to four weeks to complete. The blanching process prevents light from accessing the plant’s edible stems, leading to a more pleasant texture and flavor. To blanch cardoons, gather all the stems of the plant together in your hand, being careful to avoid the thorny leaves. Use a gloved hand to wrap the stems together inside of a piece of cardboard or ten sheets of newspaper, then tie the bundle together with a piece of twine. You can also blanch the stems by wrapping them inside an old, black or dark blue pillowcase. When three to four weeks have passed, it’s time to unwrap the stems and harvest your cardoon. Blanching is an important step in growing cardoons so don’t skip it; if you do, the flavor and texture will not be at their prime.
Harvesting & Eating Cardoons
To harvest the blanched cardoon stems, unwrap them and cut the entire clump of leaf stems off at ground level. Trim the leaf blades from the top of the stems and toss them onto the compost pile. Take the soft, succulent stems into the kitchen and get ready to cook.
Cardoon stems can be used in soups and stews like celery. They’re also delicious sautéed with some garlic, olive oil and sea salt. You can also lightly blanch the stems in boiling water and then refrigerate them and eat them with ranch dressing or a Dijon mustard dipping sauce.
How To Overwinter Cardoon Plants
Cardoon plants are hardy perennials in U.S. Department of Agriculture zones 7-10, but here in Pennsylvania, I treat the plants as annuals, harvesting them at the end of every growing season. But where they’re hardy, the plants can be grown and harvested for many years, much like an artichoke. As long as you leave the root system of growing cardoons intact, the plants will resprout a new crop of stems.
If you live north of Zone 7 and want to try to overwinter cardoon plants, surround the plants with a cylinder of chickenwire fencing that’s about as tall as the plant. Fill the cylinder with a mixture of chopped fall leaves and straw and leave it in place for the winter. When warm spring temperatures arrive, remove the cylinder and mulch slowly, a little at a time over the course of a week, until the growing point is fully exposed. With any luck, your cardoon plants will return and you’ll be growing cardoon for another delicious season.