Scientific: Cereus repandus [also known as Lophocereus schottii or Cereus peruvianus (though not from Peru) and often confused with Cereus hildmannianus]
Common: hedge cactus, Peruvian apple, queen of the night, night blooming cereus (the common names for plants in the genus Cereus are all mixed up!)
Family: Cactaceae
Origin: Brazil, Paraguay, Uruguay and Argentina (uncertain)

Pronounciation: Ser-E-us re-PAN-dus

Hardiness zones: Sunset 13, 16-17, 21-24
USDA 9 (marginal, protect from cold) - 11

Landscape Use: Strong focal point for xeric landscape themes, container plant, rock garden, large patios, and even as a natural screen for garbage containers.

Form & Character: A majestic columnar cactus, upright, tree-like, branched and contorted, convoluted, dominant.

Growth Habit: Slowly upright and branched to 20 feet (specific variants can grow to 50 feet).

Foliage/texture: Stems sometimes segmented, dull to light green, ribs mostly 12, mostly spineless to very short spines; coarse texture.

Flowers & fruits: Flowers large and white to 6" across, borne on a elongated tube, somewhat fragrant, tube short often ridged, stigma often exerted before flower opens, flowers at night; Fruits, globose, red when ripe and rounded like a small apple with a white pulp to 2.5 inches in diameter.

Seasonal color: Spectacular flower display in late spring, sometimes will flower during early fall.

Temperature: Tolerant to 20oF.

Light: Full sun and NO shade.

Soil: A well-drained mineral soil is best.

Watering: Water only occasionally if at all during summers.

Pruning: None, except to control size by occasionally thinning out awkward or crossing stem branches.

Propagation: Easily propagated from softwood stem cuttings of most any length. Will develop roots after directly planting stem cuttings into the soil (right side up!). Make sure to first allow the cut surfaces of the stems to harden for several weeks (callous over) before planting directly into soil.

Disease and pests: Susceptible to root rot in damp poorly drained soils.

Additional comments: With age, this arborescent cactus will become very large and will occupy significant physical and visual space in the landscape. The large fruit of this cactus is presently being researched as a significant fruit crop for production in arid climates like Israel. 'Cereus' is a latin word meaning 'wax' or 'torch'.

Cereus repandus and Cereus hildmannianus - A confusing tale:
Ceus repandus is very similar too, and is very often confused with, C. hildmannianus. Cereus peruvianus is not an 'officially recognized' taxon, but nonetheless is a botanical name that is 'commonly used' by many to lump together both taxa. And moreover, some taxonomist will not differentiate between the two as separate taxa and will call them both Cereus repandus. Confused yet? Don't worry. Most people, even ardent cactus enthusiasts are too.

'Monstrose' or 'Monstrosus' are botanical terms used to describe a naturally occuring mutant growth formation often resembling a contorted, club-like shape in cylindrical or columnar cacti and a wavy body shape in cacti that have flattened cladodes or pads. C. repandus form Monstrosus is often confused with C. hildmannianus form Montrosus, except that it's stems are generally a dull grayish green in color rather than the striking glaucous blue color of the stems of form Monstrosus. Here's an incredibly cool image of a severely fasciated C. repandus specimen - now that's Monstrosus!