Night-blooming cereus are diverse cacti and succulent plants known for their spectacular nocturnal blooms. These unique flowers typically unfurl after dusk, offering a brief yet captivating display before wilting by morning. Their ephemeral beauty, often accompanied by a strong, sweet fragrance, makes them a fascinating subject.
Shared Characteristics of Night-Blooming Cereus
Night-blooming cereus species share several defining features. Their most notable trait is their nocturnal flowering habit; blooms typically open after sunset and close by dawn, lasting only a single night. These flowers are usually large, showy, and predominantly white or pale-colored, helping them stand out in low light and attract nocturnal pollinators. Many species also produce a strong, pleasant fragrance.
Despite similar flowering patterns, the plants exhibit varied growth habits. Some are epiphytic, growing on other plants, while others are terrestrial, rooting in the ground. Many are vine-like or clambering, using aerial roots to climb, while some are more shrub-like or columnar.
Prominent Types of Night-Blooming Cereus
Epiphyllum oxypetalum
Epiphyllum oxypetalum, known as the “Queen of the Night” or “Dutchmen’s Pipe Cactus,” is an epiphytic cactus native to southern Mexico, Guatemala, and parts of Central and South America. This species features distinctive long, flat, leaf-like stems, often scalloped along their edges. These green stems function as primary photosynthetic organs and often sprawl or climb.
Its flowers are exceptionally large, reaching up to 12 inches (30 cm) long and 8 inches (20 cm) wide. They are pure white, funnel-shaped, and emerge from the margins of the flattened stems. The blooms are highly fragrant, emitting a sweet scent, and typically open for a single night, often between late spring and late summer.
Selenicereus grandiflorus
Selenicereus grandiflorus, also called “Queen of the Night” or “Night-blooming Cereus,” originates from the Antilles, Mexico, and Central America. This climbing cactus has long, slender, ribbed stems that can extend up to 20 feet (6 meters) or more, often trailing or clinging to supports. The green stems are typically segmented and feature small areoles.
Its flowers are among the largest in the cactus family, measuring up to 15 inches (38 cm) wide. These showy blooms are white or pale yellow, with numerous petals creating a star-like appearance. They possess an intense, sweet fragrance, often described as vanilla or orange blossom. Each flower opens for a single night, usually in late spring to early summer.
Peniocereus greggii
Peniocereus greggii, known as “Arizona Queen of the Night” or “Deer Horn Cactus,” is a desert native found in the southwestern United States and northern Mexico. For much of the year, this plant is inconspicuous, resembling slender, gray-green sticks up to 10 feet (3 meters) long. Its stems are thin, typically around 0.5 inches (1.2 cm) in diameter, and have 6-9 edges.
The plant produces sudden, spectacular white blooms that are 6 to 8 inches (15-20 cm) long and 3 to 5 inches (7.5-12.5 cm) wide. These highly fragrant flowers, often noted for a vanilla-like scent, emerge from seemingly lifeless branches. They typically bloom only one night a year, usually in June or July, and wither by morning.
Hylocereus undatus
Hylocereus undatus, recognized for producing dragon fruit, is a climbing or sprawling cactus native to tropical regions, likely from the West Indies and Central America. Its distinctive stems are triangular, fleshy, and bright green, often reaching lengths of 30 feet (10 meters) or more. These stems produce aerial roots, allowing the plant to climb for support.
The flowers of Hylocereus undatus are very large, white, and highly fragrant, opening at night. They can measure 10 to 14 inches (25-35 cm) long and up to 12 inches (30 cm) across. While cultivated for its vibrant, edible fruit, the impressive nocturnal bloom is a significant feature.
Key Distinctions Among Night-Blooming Cereus Types
Differentiating between various night-blooming cereus types involves observing their unique physical characteristics, particularly their stems and subtle flower nuances. Epiphyllum oxypetalum is distinct for its flat, leaf-like, often scalloped stems, which are notably different from the more cylindrical or ribbed stems of other species. Its pure white flowers emerge directly from these flattened stems.
In contrast, Selenicereus grandiflorus is identified by its slender, often tangled, ribbed climbing stems that produce aerial roots. Its very large, showy flowers have a more complex structure with numerous petal layers and a strong vanilla or orange blossom fragrance. Peniocereus greggii stands out for its inconspicuous, “dead stick”-like stems that blend into desert environments for most of the year, from which its sudden, large white blooms with a vanilla-like scent appear.
Hylocereus undatus is easily recognized by its robust, triangular, fleshy green stems that actively climb, and its association with the commercially popular dragon fruit. The overall growth habit also varies significantly: Epiphyllum often sprawls, Selenicereus and Hylocereus are vigorous climbers, and Peniocereus remains more shrub-like and camouflaged in its natural desert habitat.
Encouraging Blooms in Night-Blooming Cereus
Promoting abundant blooms in night-blooming cereus varieties requires specific environmental considerations. Most prefer bright, indirect light or morning sun, avoiding intense afternoon sun that can scorch stems. A spot receiving a few hours of direct morning sun and then filtered light can be ideal for encouraging flower bud formation.
A suitable watering schedule is also important. Water regularly during the growing season, allowing the soil to dry out between waterings. During cooler, dormant periods from late fall through winter, reduce watering significantly or even withhold it completely for mature plants; this can help trigger blooming. Fertilization during the growing season supports plant health and flower production. Use a balanced, water-soluble fertilizer, or one formulated for cacti, every 10 to 14 days during spring and summer.