The Night blooming Cereus is a tropical cactus. Bop ranks this plant at the top of his list as the easiest plant to care for (along with ZZ Raven). Even though Cereus is a cactus, it should not be in direct afternoon sun light. It does best with an East or West exposure with some sun in the morning or evening.
Cereus blooms in the night in June and the flowers only last one night. People have been known to throw Cereus night blooming parties complete with champagne!
The flowers are enormous with a very powerful fragrance and you can actually watch them open over a period of about 15 to 20 minutes.
Keeping the Cereus pot bound will help them to bloom. Bringing the plant outside for the summer will also help to initiate flower set. The flowers appear in the middle of the leaves.

A low Nitrogen fertilizer such as a 3-9-6 or cactus fertilizer will work. Fertilize every other week beginning in early Spring until the end of June.
Cereus requires a free draining cactus soil, or a mix of cactus soil and regular potting soil. Do not use a mix that has fertilizer in it.
Cereus needs to thoroughly dry out between watering but regular monthly watering should be carried out from Spring to Fall. Watering should be cut back severely for the Winter months. Cereus can remain dry for several months in the Winter.

Cereus is extremely easy to propagate. The plant will root from leaf cuttings or stem cuttings and it will even root on both ends of the leaf! The plant that Bop has is a cutting from a Cereus that had been handed down for three generations! This video has a demonstration of how to make a cutting.