The plants known as epiphyllum hybrids, epiphyllums, epicacti or just epis, widely grown for their flowers, are artificial hybrids of species within the group of cacti placed in the Tribe Hylocereeae, particularly species of Disocactus, Pseudorhipsalis and Selenicereus. In spite of the common name, Epiphyllum species are less often involved. The parent species from which epiphyllums were bred are different in appearance and habit from most cacti. They are found in the tropical forests of Central America where they grow as climbers or on trees as epiphytes. They have leafless (or apparently leafless) flattened stems which act as the plant's photosynthetic organs. Relatively large flowers are borne on the sides of the stems; in many species they open at night.
The Epiphyllum Society of America (the International Registration Authority for hybrids of the Tribe Hylocereeae) maintains a list of epiphyllum hybrids (and Hylocereeae species) which contained over 7,000 names in 1996.
The Epiphyllum Society of America gives some directions for cultivating epiphyllum hybrids, noting that they need different treatment from semi-desert cacti. The advice given is that epiphyllum hybrids should be protected from strong sunlight, with preferably 75% shading at midday. They are not frost hardy, so need to be protected from freezing conditions. It is recommended that the growing medium allows rapid drainage of water and is open, with at least one third of coarse material to prevent compaction. Plants should be kept moist. High nitrogen fertilizers are not recommended; no fertilizer should be given during the winter rest period.
Propagating epiphyllum hybrids from cuttings is said to be easy. Rooting hormone can be applied to the base of the cutting before it is allowed to dry for ten days or more so that the cut forms a callus. The cutting is then planted sufficiently deeply so that it can stand upright. Water is not given for two weeks, after which the growing medium is kept at least slightly moist. Plants can be misted. They should flower within two years.
- Anderson, Edward F. (2001), The Cactus Family, Pentland, Oregon: Timber Press, ISBN 978-0-88192-498-5, p. 286
- Anderson 2001, p. 101.
- Innes, C.F. (1968), Epiphytes 1: 43 Missing or empty
|title=(help), cited at IPNI Plant Name Query Results for Disophyllum, The International Plant Names Index, retrieved 2012-02-20
- Epiphyllum Society of America (2005), ESA directory, retrieved 2012-03-24 (no longer online as of September 2013[update])
- Epiphyllum Society of America (2005), About ESA, archived from the original on 2012-03-24, retrieved 2012-03-24
- Epiphyllum Society of America - the International Registration Authority for epiphytic cactus hybrids of the Tribe Hylocereeae