Origin and Habitat: Arizona (Pinal and Santa Catalina Mountains)
Altitude: 700-1000(-1500) metres above sea level.
*Habitat and Ecology: Echinocereus apachensisSN|18748]]SN|18748]] occurs in sonoran stony desert grassland and desert upland in chaparral shrublands on mineral, sandy-loamy soil. This species is common and often abundant where it occurs and there are no major threats affecting it.

• Echinocereus bonkerae var. apachensis (W.Blum & Rutow) A.D.Zimmerman
• Echinocereus apachensis W.Blum & Rutow

• Echinocereus fasciculatus (Engelm. ex B.D.Jacks.) L.D.Benson
• Cactus fasciculatus (Engelm. ex B.D.Jacks.) Kuntze
• Chilita fasciculata (Engelm. ex B.D.Jacks.) Buxb.
• Ebnerella fasciculata (Engelm. ex B.D.Jacks.) Buxb.
• Echinocereus engelmannii subs. fasciculatus (Engelm. ex S.Watson) W.Blum & Mich.Lange
• Echinocereus fendleri var. fasciculatus (Engelm. ex B.D.Jacks.) N.P.Taylor
• Mammillaria fasciculata Engelm. ex B.D.Jacks.
• Neomammillaria fasciculata (Engelm. ex B.D.Jacks.) Britton & Rose
• Echinocereus abbeae S.H.Parsons
• Echinocereus robustus (Peebles) Peebles
• Echinocereus fendleri var. robustus (Peebles) L.D.Benson
• Echinocereus rectispinus var. robustus Peebles

• Echinocereus fasciculatus var. bonkerae Thornb. & Bonker
• Echinocereus bonkerae Thornb. & Bonker
• Echinocereus boyce-thompsonii var. bonkerae (Thornb. & Bonker) Peebles
• Echinocereus fendleri var. bonkerae (Thornb. & Bonker) L.D.Benson
• Echinocereus bonkerae var. apachensis (W.Blum & Rutow) A.D.Zimmerman
• Echinocereus apachensis W.Blum & Rutow

• Echinocereus fasciculatus var. boyce-thompsonii (Orcutt) L.D.Benson
• Echinocereus boyce-thompsonii Orcutt
• Echinocereus fasciculatus subs. boyce-thompsonii (Orcutt) N.P.Taylor
• Echinocereus fendleri var. boyce-thompsonii (Orcutt) L.D.Benson

Description: Echinocereus apachensisSN|18744]]SN|18748]] is a morphological or hybrid form of Echinocereus bonkeraeSN|18730]]SN|18744]] found at the lowest altitude for the species. It distinguishes for its taller stems and unusually long (longer than 10 cm) flexible spines. Plants are very variable, as you would expect from hybrid swarm, and the parents must be Echinocereus fendleriSN|7149]] or Echinocereis fasciculatus, both common in the general area. Not at all every plant look like that. Most wild plants have their central spines shorter (like in standard Echinocereus bonkeraeSN|18744]]SN|18744]]), while some have stiffer and thicker spines. Plants usually have several brown or straw-yellow central spines with other spines white, but some plants are pure white. It is a particularly beautiful plant in flower. Flowers are crimson in colour with darker throats.
Remarks: Echinocereus bonkeraeSN|18744]]SN|18744]] (comprising var. apachensis) is a very variable and poorly defined species, frequently lumped with Echinocereus fendleriSN|7149]] or Echinocereus fasciculatusSN|18744]]SN|18730]], and it is not always identifiable in the field. All this three species vary from short-spined to long-spined.
Habit: It forms low, loose mounds of 5-30 stems up to 50 cm tall , width 1 metre branching at or before sexual maturation.
Stems: Ovoid to Cylindrical, mostly erect, green, up to 50 cm long, 4-6 cm in diameter, with spines not obscuring the stems.
Ribs: 12-18, low, not distinctly tuberculate.
Areoles: 8-20 mm apart.
Central spine: 1 to 3 per areole, very long, straight, erect, thin and flexible, mostlty descending, white to straw-yellow becoming grey, often brown to black especially at bases or tips, 1,5-10 (or more) cm long. (The standard Echinocereus bonkeraeSN|18748]]SN|18744]] has shorter spines usually less than 1 cm long).
Radial spines: 12-16, whitish, yellowish or brown, often becoming grey, spreading to almost pectinately arranged, all straight, 5-15 mm long.
Flowers: Borne on the upper half of the stems just below the shoot tips, very showy, broadly funnelform, relatively large magenta to deep purple-pink, 5-7 cm long and 4-9 cm in diameter. Flower tube 12-20 long 10-30 mm in cross section with hairs up to 1 mm long. Inner perianth segments deep magenta (to dark purple) with darker midstripes, basally very dark purple, 20-60 × 8.5-20 mm, tips relatively thin and delicate. Anthers yellow; nectar chamber 2-4 mm. There is also variation in flower shape, some plants having more E.engelmannii-like bell-shaped flowers, but mostly they are more of a trumpet shape.
Blooming season: Spring (in habitat Mar-May); fruiting 2 months after flowering.
Fruits: Globose to egg shaped, 10-25 mm long and in diameter, green, becoming red or orange red, fleshy. pulp white or pale pink.
Chromosome number: 2n = 22.

Bibliography: Major references and further lectures
1) Thomas Henry Kearney, Robert Hibbs Peebles “Flowering Plants and Ferns of Arizona” U.S. Government Printing Office, 1942
2) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
3) ames Cullen, Sabina G. Knees, H. Suzanne Cubey "The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass" Cambridge University Press, 11/Aug/2011
4) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
5) Thomas Henry Kearney, Robert Hibbs Peebles “Arizona Flora” University of California Press, 1960
6) Brian Lamb “Letts guide to cacti of the world” Letts, 17/ott/1991
7) Baker, M. 2013. Echinocereus bonkerae. In: IUCN 2013. “IUCN Red List of Threatened Species.” Version 2013.2. <www.iucnredlist.org>. Downloaded on 02 January 2014.
8) Echinocereus bomkerae in: "Flora of North America" <http://www.efloras.org> Downloaded on 02 January 2014
9) Albert Michael Powell, James F. Weedin “Cacti of the Trans-Pecos and Adjacent Areas” Texas Tech University Press, 2004
10) Edward F. Anderson "Das große Kakteen-Lexikon." Eugen Ulmer KG, Stuttgart 2005
11) Urs Eggli, Leonard E. Newton "Etymological Dictionary of Succulent Plant Names." Springer, Berlin/Heidelberg 2010
12) W. Blum, M. Lange, W. Rischer, J. Rutow in: "Echinocereus. Preprint" 1998
13) Marc A. Baker, Jon P. Rebman, Bruce D. Parfitt, Donald J. Pinkava, Allan D. Zimmerman "Chromosome Numbers in Some Cacti of Western North America-VIII." In: Haseltonia. 15: 120 2009

Cultivation and Propagation: In culture Echinocereus apachensisSN|18748]]SN|18748]] presents no difficulties, but grows rather slowly and is sensitive to over-watering (rot prone).
Watering: It needs very good drainage to avoid rotting, but requires more moisture than true desert cacti, to grow and produce flowers. Keep drier and cool in winter.
Exposure: It needs full sun.
Hardiness: It's cold resistant to -10° (or less, depending on clones) for short periods of time.
Uses: It is a fine plant for a rock garden or container, and contrasts well with agaves, yuccas, and low-growing flowering plants. It will show its flowers only provided with an adequate winter rest period.
Propagation: Seeds, can also be grown from cuttings, as it branches from the base. When grown from wild seeds it is a good idea to keep as many plants as possible until they mature, and then select the most remarkable plants to keep in the collection.