Cereus repandus aka Peruvian Apple Cactus

Cereus repandus is a fast-growing columnar cactus that can reach impressive dimensions. Young plants grow more than 30 cm (12 inches) per year. At maturity, it typically reaches 10 meters (33 feet) tall, though specimens over 12 meters have been recorded. The plant branches from the base and can spread 3-5 meters (10-15 feet) wide. The cylindrical stems are grey-green to blue-green, measuring 10-20 cm in diameter with 9-10 rounded ribs.

Cereus repandus is cold-hardy for a cactus, tolerating temperatures down to -5°C (18-20°F) for short periods. Ideal growing temperatures are 18-29°C (65-85°F). During winter dormancy, keep above 5-8°C (41-46°F). In zones 9-11, it can be grown outdoors year-round. Below these zones, protect with frost blankets or bring indoors during cold spells. Avoid cold drafts when grown as a houseplant.

Cereus repandus produces spectacular nocturnal flowers from late spring through early fall. The large, funnel-shaped flowers measure 12-15 cm (5-6 inches) across with creamy-white petals and reddish tips. Each flower opens for only one night and closes by morning. The flowers are pollinated by bats, which are attracted to their nighttime blooming habit. After successful pollination, thornless fruits develop and ripen in 40-50 days.

Cereus repandus is primarily bat-pollinated (chiropterophily). The large, cream-colored flowers open at night and emit a fragrance that attracts pollinating bats. Each flower remains open for only a single night, making bat pollination essential for fruit production. In cultivation, hand pollination may be necessary if bats are absent. The flowers can also attract nocturnal moths as secondary pollinators.

The most popular variety is Cereus repandus 'Monstrosus' (also sold as Cereus peruvianus 'Monstrosa'), known as the Curiosity Plant. This mutant form produces thick, irregularly shaped stems with a fascinating sculptural appearance. It stays shorter than the species, making it more suitable for container growing and indoor cultivation. It still produces the same delicious, edible fruits. Hardy in USDA zones 9-11.

Cereus repandus thrives outdoors in USDA zones 9-11 where temperatures stay above -5°C (20°F). It prefers full sun with at least 6-8 hours of direct sunlight. In borderline zones (9a), provide frost protection with blankets or mulch over the root zone during cold snaps. The plant grows naturally in seasonally dry tropical climates and tolerates heat and drought well. In cooler climates, grow in containers that can be moved indoors for winter.

Prune Cereus repandus in autumn when new branch production stops, or when the plant becomes overgrown. Use a pruning saw rather than pruning shears to cut through the thick, ribbed stems. Always wear thick protective gloves due to the numerous spines. Allow cut surfaces to dry and callus over naturally, which helps prevent rot and disease. Pruned sections can be used for propagation after the cut end has calloused for 1-2 weeks.

Repot young Cereus repandus every 1-2 years in spring as they grow quickly. Mature plants need repotting less frequently, typically every 3-4 years or when roots become crowded. Choose a pot only slightly larger than the previous one, with excellent drainage holes. Use a well-draining cactus mix with added sand or perlite. Repotting is a good opportunity to refresh nutrients with slow-release fertilizer. Handle carefully due to spines and allow the plant to settle for a week before watering.

Cereus repandus propagates easily from stem cuttings or seeds. For cuttings, take a section of stem and allow the cut end to dry and form a callus for 1-2 weeks. Plant in well-draining cactus soil and keep barely moist until roots develop. Basal offsets (pups) can be separated and propagated similarly. Seeds germinate in 14-28 days at 25°C (77°F), though seedlings grow slowly. Cuttings are faster and more reliable than seed propagation.

The most common pests are mealybugs, scale insects, snails, and slugs. Remove mealybugs with rubbing alcohol on cotton swabs or use organic insecticidal soap. Root rot is the primary disease concern, caused by overwatering or poor drainage. Signs include mushy, discolored stems at the base. If rot occurs, cut above the affected area with a sterile knife, let the cut callus for two weeks, then replant in fresh, well-draining soil.

Yes, Cereus repandus produces delicious edible fruit called pitaya or Peruvian apple. The thornless fruits ripen from violet-red to yellow with sweet, white flesh containing small crunchy seeds. They can be eaten fresh, added to fruit salads, made into jams, or used in smoothies. The stems are also edible and traditionally prepared as soup or cooked with vegetables in Caribbean cuisine. Fruits are rich in vitamin C, beta-carotene, and dietary fiber.

Cereus repandus has documented traditional medicinal uses in various cultures. In South America, the dried green flesh between the skin and fruit is used to treat diarrhea. In northeastern India, the roasted fleshy stems are squeezed to extract juice for treating coughs, often mixed with honey. Scientific research has identified anti-obesity, anti-ulcer, antiproliferative, and antioxidant properties. The plant contains alkaloids, saponins, glycosides, and omega fatty acids.

Beyond ornamental cultivation, Cereus repandus has numerous practical uses. The Wayuu people of Colombia and Venezuela use the inner cane-like wood for wattle and daub construction. The plant is widely used as living fences and hedges in its native range. The wood serves as furniture material and firewood. In Curaçao, it has been used as shampoo and soap. Modern applications include carbon farming for environmental benefits and as drought-tolerant livestock fodder.