Echinopsis

Echinopsis is a genus of cacti native to South America, sometimes known as hedgehog cactus, sea-urchin cactus or Easter lily cactus. , there are about 20 accepted species, ranging from large and treelike types to small globose cacti. The name derives from echinos hedgehog or sea urchin, and opsis appearance, a reference to these plants' dense coverings of spines.
They are remarkable for the great size, length of tube, and beauty of their flowers, borne upon generally small and dumpy stems.
Taxonomy
Studies in the 1970s and 1980s resulted in several formerly separate genera being absorbed into Echinopsis. When very broadly circumscribed, Echinopsis sensu lato included over 100 species. Some genera have been absorbed and then accepted again. For example, the genus name Trichocereus was given to a number of columnar cacti in 1909 by Vincenzo Riccobono. The genus was subsumed into Echinopsis in 1974 by Friedrich, along with Lobivia. In 2011, it was argued that Trichocereus was distinct from Echinopsis, and a 2012 genetic and morphological study by Albesiano found Trichocereus to be monophyletic if it included three species of Harrisia.
A 2012 genetic analysis of chloroplast DNA indicated Echinopsis was made up of several divergent lineages. This was shown again in 2019.
, Plants of the World Online accepts Echinopsis more narrowly circumscribed to include only about 20 species.
Species
Species as according to Plants of the World Online :
Many hybrids exist, mostly between similar species but also between more distinct ones, such as the cross between Trichocereus pachanoi (now Trichocereus macrogonus var. pachanoi) and E. eyriesii (now E. oxygona) which was sold under the name "Trichopsis pachaniesii" by Sacred Succulents.
Distribution
Echinopsis species are native to South America (Argentina, Bolivia, Peru, Brazil, Paraguay and Uruguay). They grow only in situations where the soil is sandy or gravelly, or on the sides of hills in the crevices of rocks.
Cultivation
The growing and resting seasons for Echinopsis are the same as for Echinocactus. Research by J. Smith (former Curator at the Royal Botanic Gardens, Kew) showed that species like the Chilean Echinopsis cristata and its Mexican relatives thrive if potted in light loam, with a little leaf mould and a few nodules of limestone. The limestone keeps the soil open; it is important that the soil should be well drained. In winter, water must be given very sparingly, and the atmosphere should be dry; the temperature need not exceed during the night, and in very cold weather it may be allowed to fall to , provided a higher temperature of is maintained during the day. In spring, the plants should receive the full influence of the increasing warmth of the sun; and during hot weather, they will be benefited by frequent spraying overhead, which should be done in the evening. The soil should never be saturated, as the soft fibrous roots will rot if kept wet for any length of time.
None of the species need to be grafted to grow freely and remain healthy, as the stems are all robust enough and of sufficient size to take care of themselves. The only danger is in keeping the plants too moist in winter, for although a little water now and again keeps the stems fresh and green, it deprives them of that rest which is essential to the development of their large, beautiful flowers in summer.
Gallery
References
Bibliography
Edward F. Anderson, The Cactus Family (Timber Press, 2001) , pp. 255–286
K. Trout, Trout's Notes on San Pedro & related Trichocereus species (Sacred Cacti 3rd ed. Part B) (Moksha Press, 2005)
External links
Cactus Culture for Amateurs by W. Watson (1889)
Cactus Culture Volume 1: Trichocereus by Patrick Noll
SucculentCity: Plant Profiles, Photographs & Cultivation Data
Kuentz: Echinopsis (in French)
Lohmueller: Echinopsis
Mattslandscape; Echinopsis hybrids-growing culture
Vimeo Video Echinopsis Cacti in Bloom
echinopsis.com Photographs, Videos
Echinopsis Cacti Flower Photographs, Videos
Cacti of South America
Cactoideae genera
Articles containing video clips