This mouthful of a plant, named after the Kochubeys, a Ukrainian noble family of Crimean Tatar origin, was the #1 target species of my trip to central Mexico in October 2017. The miniature Ariocarpus kotschoubeyanus var. kotschoubeyanus grows in the Mexican states of Couahuila, Nuevo León, Zacatecas, Tamaulipas, and San Luis Potosi. The slightly larger subspecies elephantidens grows in a much more restricted area in Querétaro (see map below). I saw it in a couple of locations northwest of the Zimapán reservoir around Mesa de León. Other cacti growing in that area were Ferocactus latispinus, Echinocereus cinerascens, Coryphantha cornifera, Echinocactus platyacanthus, Thelocactus leucacanthus and Pachycereus marginatus. Despite having received coordinates of where to look for this Ariocarpus I probably wouldn’t have found the plants, had they not been in flower!
The photos of individual plants show that these grow almost flush with the ground, and blend in well. Ariocarpus kotschoubeyanus subsp. elephantidens grows up to 7-8 cm in diameter, flat on top and with a depressed centre. The tubercles are broadly triangular, 5-13 mm long and up to 10 mm wide. The areoles are woolly furrows that extend the full length of the tubercle. The flowers are magenta and appear at the centre, singly, or in pairs.
I bought a small plant of Ariocarpus kotschoubeyanus var. elephantidens from a well-known Czech cactus nursery before Brexit made such imports difficult and costly or impossible. It is currently about 6 cm in diameter and is growing in a 2.5” plastic pot in the sunniest corner of my greenhouse. The substrate is a third John Innes #2 and two-thirds of horticultural grit and some limestone chippings. I water all my Ariocarpus from April to September, fortnightly in April and September, and weekly from May to August. I add a low-nitrogen feed to every other watering. I don’t repot my Arios until I can see that the growth of the tap roots makes the pot bulge, but that is probably leaving it a bit late!
My small greenhouse can get very hot in summer, despite the door being left open and automatic roof vents. A fan comes on when the temperature exceeds 24C. In winter, an electric heater with a thermostat maintains a minimum temperature of 6C.
I am fascinated by the fact that despite hugely different growing conditions my Ariocarpus kotschoubeyanus var. elephantidens flowers almost to the day at the same time as the plants that I saw in habitat in Mexico. The photos of my plant were taken on 22/10/2019 and 25/10/2021, and those in habitat on 22/10/2017! To avoid the risk of fungal infection getting into the body of the plant it is recommended to remove the spent flowers, but I usually don’t have to do that because snails in my greenhouse eat them! I have never had fruits on my plant.
Text & photos by Dr Frank Sengpiel
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