Description for Acanthocereus tetragonus Plant height: 2 - 4 inches Plant spread: 1 - 3 inches Acanthocereus tetragonus is a tall, columnar cactus. Stems are dark green, have three to five angles. Flowers are open from midnight until dawn, attracting hummingbird moths. Common name(s): Fairy Castle Cactus, night-blooming cereus, barbed-wire cactus, sword-pear, dildo cactus, triangle cactus Flower colours: White Bloom time: Rainy season Max reachable height: Up to 2 to 7 M Difficulty to grow: Easy to grow