Two plants are called night-blooming cereus:
One is a night blooming, fragrant epiphytic cactus, classified as Hylocereus due to the TRIANGULATE leaves, and upright growth to 15′. Selenicereus grandiflorus is commonly called night-blooming cereus or Queen-of-the-Night. The leaves look like squared off – three point versions of prickly pear with numerous, repetitive spines on the edges. True Cereus species are rounded stemmed and usually have tiny leaves. Flowers have funnel shaped interior petals, with daisy-like exterior petals.
Another is an Epiphyllum; also a night blooming cactus species but with a shrubby, prostrate, almost cascading characteristic and an overall height of 8′ max in the wild. Leaves look almost smooth, are very long,… FLAT…. and have spines only on the margins at the indentations. Flowers are very petalous. Most common one is Epiphyllum oxypetalum.
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CARE: Bright shade, low fertility, careful watering. Segments of Epiphylum can be rooted by inserting the lower third in potting soil.