Cardoon (Cynara cardunculus) is a herbaceous plant which belongs to the family of Asteraceae. This is a ancient vegetable which was already cultivated in antiquity, but unfortunately fell into oblivion. It is very close to the Artichoke, both belonging to the same botanical family. Cardoon is grown for its cards which are none other than meaty ribs harvested in autumn. They are nutritionally beneficial. Well supplied with minerals, trace elements, vitamins B9, C, and fiber, they are also low in calories, rich in water and have a diuretic effect. Cardoons have a good taste of artichoke with a hint of bitterness, but some precautions should be taken when growing Cardoon so that they do not become too bitter.
It is possible to sow under cover cardoon seeds between February and April. You can use small biodegradable pots, boxes or crates in which you sow in little bits of 4 seeds, 5 at most. But if you opt for this solution, it will be necessary to transplant the seedlings as soon as they have formed at least 3 leaves and when all risk of late frost has passed. Note that the sowing in place are quite possible provided that we wait until the month of June.
When the first true leaves are formed, we move on to transplanting whether you have opted for sowing under shelter orthinning in the case of sowing in place. The gardener must keep only the most beautiful plant of each pocket, that is to say the one which is distinguished from the others by its great vigour.
If you do not want to take care of the seedlings, it is of course possible tobuy cardoon plants to transplant them directly into the ground from mid-May, when the ground has been sufficiently warmed by the spring sun. However, it is not so easy to find…
Cardoons need to be planted 30 cm deep. They need more lots of space to develop because at maturity they are large plants that can reach 2 m in height and 80 cm in wingspan. This is why when planting in place, care must be taken to space the seedlings sufficiently apart, namely 90 to 100 cm. It is also advisable to respect a satisfactory interval between two rows, of the order of 140 to 150 cm in order to be able to subsequently access its crops without any difficulty.
Before installing cardoons in the garden, we start by loosen the earth by digging about 50 cm deep. Take the opportunity to remove stones, weeds and their roots, then enrich the soil with well-ripened manure or compost so as to meet the great needs of these gourmet vegetables.
The Cardon likes loose, humus-rich, deep, well-drained soils. He particularly appreciates being installed under the sun. The type species has large spiny leaves but there are spineless varieties, that is to say without thorns, which are beginning to attract more and more gardeners. The method of cultivation is the same for all.
The Cardon can quickly become invasive because he reseeds itself spontaneously and is able to regrow well beyond the vegetable patch, for example in neighboring gardens, meadows and nearby cultivated fields, which is not always to everyone’s taste!
Caring for Cardoon
It is not very complicated to cultivate cardoons. Excellent results are obtained if the following points are respected.
It is important that the cardoons have always cool feet. Humidity promotes recovery. Of the regular watering are therefore essential after sowing and throughout the cropping period. You have to be vigilant in summer or in the event of severe drought. Be careful, however, of do not drown its ranks! It is known that excess water leads to rotting of the root system of the majority of plants. Cardoons that benefit from soil that is always fresh but not soaked promise good harvests.
A contribution of compost for example during cultivation is welcome.
Although they are very pretty, the Cardoon inflorescences greatly exhaust the plant. Except if one cultivates this plant for its decorative aspect, or if one wishes to recover its seeds, it is recommended to eliminate the flowers progressively.
Put a mulch at the foot of the cardoons a little before the first frosts if it is not already done is essential because these plants are chilly. They do not support temperatures below -6 or -7°C. A generous layer of grass clippings and previously dried dead leaves is an excellent solution to avoid the hazards caused by the early cold which can be biting in some of our regions… and therefore fatal for these vegetables.
If you want to be able to taste chard without bitterness and very meltingit is absolutely essential to carry out their whitening. To do this, we must tie the Cardoon leaves together approximately one month before harvest, i.e. early September at the latest. The frequently used method is to collect all the leaves with the same foot by raising them then bind them with raffia or twine. Be careful not to overtighten the ties because the air must be able to continue to circulate in order to limit the risk of rot due to the higher humidity at this time of the year. This simple gesture allows to obtain the etiolation of the leaves by deprivation of light.
Other bleaching methods exist. One is to butter the feet on 25 cm then to swaddle each plant in carton leaving only the end of the tuft of leaves sticking out. It is necessary to tighten the raffia or the string well around the cardboard so that it is perfectly maintained. A geotextile film perfectly replaces cardboard, but is more expensive. The other solution is limited to turn over large terracotta pots on the cardoons, which generally results in bleaching of the ribs in about twenty days.
As we have seen, the Cardon is not very hardy. It must therefore be blanched not on site, in the vegetable garden, but a cave in regions with a harsh climate because the frosts there can be early and severe to the point of ruining an entire crop and depriving the gardener of his harvest. L’anticipation is therefore in order since it takes about a month for the cards to have time to whiten.
Also, in these particular geographical areas, the best way is topull out the cardoons as soon as the mercury indicates 0°C. Then simply install them under sand, in a frost-free, well ventilated and dark cellar. Storage in a gauge suits them well, exactly as for endives. Of course, if you opt for this solution, the ribs will all be consumed at the same time or almost. If a large quantity has been harvested, it will be necessary to opt for their preservation in jars so as not to lose them. This is the best solution to keep them for a while and preserve their taste quality.
Pests and diseases
Cardoon is a vegetable garden plant that poses few problems since it is not not very sensitive to parasites et illnesses affect him little. However, it happens, as with Artichokes, that oily spots appear and then turn brown. This disease, called artichoke fat, requires the uprooting of all affected parts, even the entire plant, which must then be burned, because no solution can eradicate it.
More generally, to protect your cardoon crops against possible pests and diseases that are always possible, you can preventive treatment with sprays on the leaves of horsetail decoction to avoid mildew, and nettle manure to avoid being bothered by aphids. All treatment must of course be stopped at least four weeks before harvest..
Finally, let us know that even if it is little affected by parasites and diseases, the cardoon is essentially sensitive to excess humidity, especially during the whitening period. Hence the interest of not over-tightening the string that holds the leaves together.
Harvesting cardoons from the vegetable garden
As we have seen previously, it is only Cardoon chard or ribs that we consume. They are prepared a bit like Swiss chard to obtain an ultra melt-in-the-mouth and absolutely delicious vegetable, especially if care has been taken to blanch them. Harvesting of chard can begin around 5 months after sowing. Simply use a knife to slice the base of the cardoon.
As long as it does not freeze, this ancient vegetable can be harvested as needed because, alas, its the duration of the conversation is short. It only lasts a few days in the vegetable compartment of the refrigerator, provided that the chard has been wrapped in a clean tea towel or in a cloth bag. However, it can be kept for two months, in a totally blind, cool place, and only if the entire root ball has been kept.
Attention, cardoon leaves are not eaten. They are thorny, which gives this plant the look of a large thistle which is nicely adorned with large, very decorative mauve to purplish blue flowers (not edible either). They recall the flowers of the Thistle and those of the Artichoke. Moreover, thistles, artichokes, cultivated cardoons and wild cardoons (original form of the artichoke) are part of the same botanical family and have many points in common. They are so close to each other that they can hybridize in nature, quite spontaneously. The species in which we are particularly interested here is the cultivated cardoon (Cynara cardunculus was. tall).
After being long forgotten, the Cardon returns to the menu, prized even by restaurateurs. Tasty, it is prepared, for example, as a gratin, accompanied by a good béchamel sauce, and that’s not to mention chard with marrow cooked the old-fashioned way, a Lyon gastronomic specialty which is worth the detour.