If you love artichokes and don’t mind the work involved in preparing them, you’ll fall head-over-heels in love with cardoons. While you don’t see them growing in too many gardens yet, that’s quickly changing.
Related to, and very much tasting like an artichoke, cardoons look like a giant celery stalk covered in tiny spikes.
At first glance, cardoons don’t look appetizing, but don’t be put off. Hiding behind that tough exterior, you’ll discover the creamy delicacy inside.
Ready to get started?
Varieties of Cardoons
Cardoons can grow up to six feet tall. The plant has large, silvery, grey leaves and purple thistle-like flowers. Some gardeners grow them for aesthetic purposes only, because are beautiful in floral arrangements.
I have them planted on unused banks to add to my variety of culinary options.
Cardoon seeds are often sold under the generic term of “heirloom’ variety. Sometimes the cultivar is stated. If so, it will likely be one of the following:
Cardon de Tours
This is the variety I would recommend to all gardeners new to growing cardoons. It’s a small variety, so it does well in gardens and areas with less space available. It has the creamiest, subtle taste of all the varieties I’ve tried.
Preparing cardoons for cooking can be a bit of a challenge because of the prickles on the leaves. The Spanish variety has fewer spiky bits, which makes for easier harvesting and preparation in the kitchen. This is a medium-sized cardoon and is suitable for small to medium spaces.
The leaves of the red variety are longer and more slender than other varieties. The pink ribs are large and look fantastic when cooked, though some fading is likely, depending on your cooking method.
This is often the most common variety available. It grows to between five and six feet tall. I find the common variety doesn’t have the quality of flavor as the other types and the stems were hollow on a few plants one season.
It’s still a good option for the home gardener because its reliable and sturdy.
A good home variety that is reliable and seeds are readily available. Great for growing cardoons as an annual because it matures quickly.
Ivory White Smooth
This is another popular home variety. It’s good for growing as an annual in slightly cooler areas because it doesn’t take as long to mature as some other varieties.
How to Grow Cardoons
Cardoons originated in hot regions and they grow as a perennial in USDA Zones 7 to 10. In cooler climates, grow them as an annual.
The plants should get full sun, but they will tolerate partial shade as long as it’s getting at least 6 hours of sunshine.
Make sure your soil is full of well-rotted organic matter. Dig it in deep prior to planting if your soil is lacking. Cardoon grows best with a soil pH of 6.0 to 7.0. The earth should be well-draining because this plant can’t tolerate wet feet.
Three weeks before you plant cardoon, dig in well-rotted manure and organic matter. Aged compost works best with cardoons.
Cardoons don’t do well growing in containers. They like a lot of space for their roots. If you do grow in a container, choose at least a five-gallon pot. Plant one cardoon per pot.
Use potting mix especially designed for vegetables and water the plant regulrarly and well.
Starting Seeds Indoors
Start seeds inside six weeks before you want to plant out. Use individual pots and use a good quality seed raising mix.
Plant cardoon seeds about a 1/4 inch deep and cover lightly. Keep the seeds moist until germination, then gradually increase the amount of water as the plant grows. Transplant when the seedlings are between 4-6 inches tall.
Cardoons germinate best at about 70°F to 75°F.
Starting Seeds Outdoors
You can plant directly into the garden anytime after the frost, so long as you have a good 100 days of frost-free growing ahead. The seed germination rate outdoors is reasonably high.
Plant seeds at a depth of 1/4 inch deep and cover with a cloche until the seedling is well established. Thin seedlings so that you have one plant every 24 inches or so.
They aren’t always easy to find at the nursery, but you can put transplants in the garden about four weeks after the average date of your area’s last frost. Make sure any risk of frost or cold snaps has passed before putting the transplants out.
Plants should be 18 to 24 inches apart and rows 24 to 36 inches apart. Cardoon need space to spread their leaves and still have sufficient airflow between each plant.
Caring for Cardoons
You’ve got your seedlings looking happy, but how do you keep your newly growing cardoons happy in the garden? There are a few things you should know.
You worked in plenty of well-rotted manure or compost when planting, right? That’s all you need to do for food in the first year. Once the plant is in full growth, it generally won’t need any more feeding.
If you’re growing cardoons as a perennial, feed with a side dressing of well-rotted manure in late winter to early spring.
Water cardoons deeply but infrequently. Only water the soil, not the leaves, and allow the ground to dry out for the first inch or so before watering again. Cardoons don’t like wet feet.
Cardoons don’t appreciate wind. The leaves get large and can easily tear in strong winds. Protect by planting in a sheltered area.
The only reason you would prune cardoon is because you are harvesting the leaves or a leaf is damaged and dying.
Towards the end of their growing cycle, cardoons need to be blanched to make them more flavorful and tender. Some people don’t do this, so if you want to see if it makes a significant difference to you, blanch some stalks and leave some natural.
To blanch, three weeks before harvest, tie the leaves together in a bunch and wrap the stems up to about 18 inches. Burlap is best. You can build the soil up in place of wrapping the stems, but this is messy and hard work.
Companion Planting for Growing Cardoons
Plant cardoons with perennial vegetables like:
- Globe artichokes
Common Problems and Solutions for Growing Cardoons
Cardoons face many of the same pests and diseases that artichokes struggle with.
In addition to the all-too-familiar aphid and snails, you also need to watch out for moths.
Aphids: These sap-sucking insects not only damage every plant they live on, but they spread quite a few diseases as well. They excrete honeydew, a sweet substance loved by wasps and ants. Honeydew often develops sooty mold.
Try and prevent aphids from getting a hold in the first place. Use neem oil as soon as you see an aphid.
Artichoke Plume Moth: This large moth with a wingspan of up to 1 and 1/2 inches is a real danger to artichoke, cartoons, and many other crops. It can lay up to 245 eggs on the undersides of leaves, close to unopened buds.
When the larvae hatch, they start eating the leaves, buds and stems.
Inspect your cardoons regularly and if you think you have an infestation, remove the affected part of the plant straight away and burn it. You can also seal it in the household trash.
Neem oil or a pesticide that contains pyrethrins are good ways to keep this pest under control.
Slugs and Snails: The most common pests of cardoon are snails and slugs. I use snail pellets with a bittering agent to prevent animals from eating them. Snails and slugs don’t do a lot of damage, but they are more destructive when the cardoon is small.
There aren’t too many diseases that plague cardoons, but the most common one can be a real problem if it strikes.
Artichoke Curly Dwarf Virus: This is a devastating virus for cardoon. The plant will lose vigor and be stunted dramatically. The leaves usually distort and have dark spots all over them.
Use disease free plants to prevent the disease. Aphids spread the disease so control them as best you can with neem oil and pyrethrum. Remove and destroy any infected plants.
When you get rid of the aphids, the disease is easier to address.
Harvesting and Using Cardoons
When you are ready to harvest, make sure you have time set aside because the process may take a while. It’s worth it though.
Get some thick gloves because you don’t want to be pricked by the spikes. I use a towel to hold the stem while I prepare it for cooking.
If you want to take just a few and leave the rest of your cardoons growing, cut the stems off at a few inches above ground level and trim off the leaves to keep the stem. It will be quite thick and ribbed, much like celery.
You can also dig down and slice the entire plant off at the top of the root.
To prepare, peel the ribs off like you would celery. I prefer to use a sharp knife. Turn the stem over and scrape the thin layer of skin off. This video can help:
The cardoon is now ready for cooking. It pays to blanch the prepared stems in boiling water for about 15 minutes, before plunging in ice water.
Cardoons can be fried, braised, added to stews and casseroles, used in desserts, and salads. It can be preserved in brine and simply cooked in wine, oil, and butter, with a little salt.