JARDÍN BOTÁNICO
San Miguel
de Allende
Guanajuato, México
charcodelingenio@gmail.com
Mexico has the richest variety of cacti in the world as well as many plants from other succulent families, with often strange forms and surprising colors. Until recently these plants have been little known or appreciated except by botanists and collectors. Many are rare and in danger of extinction. As in other parts of the world, threats to their survival include changes in land use, urban expansion and illegal collecting and trafficking for the collectors market.
El Charco del Ingenio sees the conservation of this natural and genetic heritage as one of its primary objectives. For that reason, we began to build up a collection of Mexican succulents from diverse plant families in order to showcase the variety that exits in our country and to draw attention to the threats they face. The inspiration for this came from the late Charles Glass, well known cactophile and curator at the Botanical Gardens, who carried out much of the initial collection work before his death in 1998.
Most of the botanical collection is made up of plants gathered from all parts of the country along with others propagated in the nursery at the Botanical Gardens, plus a number of donated plants. This extensive work of collection has meant building links with rural communities, scientific institutions, and a close relationship with the federal authority. The Mexican Environmental Agency (SEMARNAT) has recognized the Charco del Ingenio Botanical Gardens as the legal depositary for the collection, under the category of Unidad de Manejo para la Conservación de la Vida Silvestre (UMA).
The botanical collection at El Charco del Ingenio represents the richness and biodiversity at risk in our country. It is exhibited mainly in the Conservatory of Mexican Plants, along with aquatic species and native fish. El Charco del Ingenio also uses the plants as the basis for propagation in its nursery, and plants are on sale at the Botanical Gardens Visitor's Center.
Although made up of plants from many plant families, most of the collection consists of Cactaceae (Cacti) and Crassulaceae (Stonecrop), two families of which Mexico has a wealth of native species.
Plants in the collection of Cactaceae range in size from large columnar and barrel cacti to shrubby and clustering plants and many smaller species with dazzling flowers. Amongst the larger plants, several are of particular interest. Cephalocereus senilis, with its stems covered with long white hair, is known as the "old man cactus." In the wild, they grow upto 15 meters high. At the entrance of the Gardens, we have planted a traditional fence of Pachycereus marginatus, commonly known as "organ cactus." Its thick but weakly thorned stems make an attractive but effective barrier, while "creeping devil" (Stenocereus eruca), its stems covered with dagger-like thorns, grows along the ground, rooting as it goes.
The larger barrel cacti include Echinocactus grusonii, or "golden barrel," some 200 of which are planted as a cascade on a hillside in the Botanical Gardens. Ferocactus histrix -acitron- is native to the area, but we also have many large specimens that have been imported into the Gardens as rescued plants. In this case, the threat to their survival was their use in making cactus candy. The largest of all the barrel cacti is Echinocactus platyacanthus, with its massive stems up to 2.5 meters tall. Two huge specimens have been imported into the Gardens as rescued plants.
Shrubbier species include a variety of Opuntias, or prickly pears and their relatives. Some are very fiercely thorned and many are eaten, as fruit and as young stem sections, boiled as a traditional Mexican dish known as nopales or nopalitos. Some of the most spectacular sights in the garden are several species of Echinocereus. Their thick clustering stems form clumps up to a meter or more across, covered by a mass of large, shiny pink flowers in the spring.
Climbing and trailing species are also abundant in the Gardens. Many of these plants, such as Selenicereus sp., "Queen of the Night," Peniocereus serpentinus and several species of Acanthocereus, have large, white nocturnal flowers.
Among the low-growing plants in the collection, the genus mammillaria is notable for its range of forms and flowers, often arranged in rings around the plants. This genus of about 180 species is well represented, including larger plants such as Mammillaria melanocentra, M. compressa, M. magnimamma and M. spinosissima. A smaller species, Mammillaria marcosii, is one of the discoveries made by the Botanical Gardens under the curatorship of Charles Glass. It is a beautiful plant with a wide range of thorn colors. The large clusters of Mammillaria plumose are impressive with thready thorns like cotton wool. Miniature plants include M. albiflora with dense white spines, and M. saboae s.p. goldii, with large flowers. Mammillaria luethyi is a recently discovered species, a tiny plant, bearing large flowers.
In addition, the Botanical Gardens has a wealth of plants from other genera. Astrophytum ornatum is impressive, with speckled stems up to 1.5 meters tall. A. myriostima, a squat, thornless plant is covered with tiny woolly spots. Ferocactus emoryi ssp. rectispinus has the longest thorns of any plant in the collection, up to 18 cm long. Some eight hundred Pelecyphora asseliformis are planted in and around the Conservatory, their low bodies camouflaged in the gravel. These plants were rescued from a road-widening project some years ago.
The genera Coryphantha, Echinocerus and Thelocactus are well represented in the Gardens, as well as Ariocarpus, Obregonia, Epithelantha, Turbinicarpus, Aztekium, etc., including specimens of Geohintonia mexicana, a new genus discovered in the last decade and whose holotype is kept in the garden’s nursery.
Amongst the Crassulaceae, the genus Echeveria predominates. These rosette-shaped succulent plants have a wide range of colors, from almost black in E. affinis to pink in E. lilacina and including green, grey and blue. Some echeverias, such as E. cante and E. lauii have leaves covered with a thick powdery wax coating. Dudleya has large rosettes of dazzling white, while genera such as Sedum (siemprevivas) are creepers that form mats below the other plants.
The other succulent families include Cycadaceae, Bombaceae, Euphorbiaceae, Bromeliaceae and a large number of Agavaceae (century plants). Many plants of this last family have economic uses, such as the making of wines and distilled drinks and as a source of fibers. The leaf bases of Dasylirion acrotriche (cucharilla) are used locally as decorations for religious festivals. Many of these plants are found and used in the Gardens, emblematic of the integration of the botanical and cultural interests of the Charco del Ingenio.