Night blooming cereus (Cereus greggii) is a vine-like cactus native to southern areas of the desert southwest and northern Mexico. They bear extraordinary white flowers, which open after dark, and are delicately fragrant. The flowers last only a single night, and the flowering period is brief, so that all the flowers from entire populations bloom simultaneously over one to three nights. These plants can grow to be quite large, and need sturdy support of trees, trellises or fences. Night blooming cereus grows best outdoors, in areas where winter temperatures do not dip below freezing.
Select a healthy stem from a cultivated night blooming cereus. Wear gloves to protect your hands from the spines, and remove the bottom six to eight inches of the stem with the sharp knife. Look for naturally-occurring segments on the cactus stem and, if possible, make the cut there.
Place the cutting on a sheet of old newspaper and allow it to dry in a well-ventilated place, out of strong sunlight, for two to four days until a firm, tan to brown callous appears on the cut end of the stem.
Fill a clean one gallon pot with a mixture of one part well drained potting mix to one part coarse sand, and then gently firm with your hands. Place the bottom 1 to 2 inches of the cutting into the soil mix.
Drive a thin bamboo stake into the pot, avoiding the cutting, and any existing roots. Secure the cutting loosely to the stake with one or two twist ties, so that it will not move as it makes roots.
Place the pot in a protected place where it will receive bright shade. Wait until the night blooming cereus has new growth to move your plant into partial or full sun.
Water the pot just until water runs out the bottom at planting time but do not water the pot again until you see new growth emerge from the cutting. Fill pots with actively growing plants with enough water to cover the soil surface and allow it to drain, and then fill the pot once more. Water mature plants once every two weeks in the warm months, allowing the soil surface to dry between waterings. Water the plants only once a month in winter.
Feed your established night blooming cereus with a balanced liquid plant food, diluted to half strength, once a year in early March.