The Epiphyllum oxypetalum is most commonly known as Dutchman's pipe cactus. It's also known as night-blooming cereus and queen of the night. This tropical cactus is not a very attractive plant, but when it blooms it catches everyone's attention. The white blooms can be up to 11 inches long and 5 inches wide. What is most unique about the plant is that the blooms open in the evening and close up by sunrise. You can grow Epiphyllum oxypetalum in USDA zones 10 through 12 or in containers and hanging baskets that can come indoors or go in a greenhouse for the winter in other zones.
Choose a location that is partially shaded for plants going in the landscape. If planting in a container, full sun or slight afternoon shade is best. Dig a hole twice as wide and 2 inches deeper than the root ball.
Mix 1 part compost, 2 parts peat moss, 1 part coarse sand and a little bit of small pine bark to make up the potting or growing soil. Fill container to an inch of the top with the mixed potting soil and then push the soil away from the center to make room for the plant. If planting directly into the landscape, mix in a couple of handfuls of the original soil and place 2 inches of the amended soil on the bottom of the hole.
Take the plant out of the original container and knock off most of the soil from around the roots. Place in the ground or in the container and fill soil in around the root ball. Press down firmly to compact the soil around the roots. The plant should be planted at the same level it was in the original container.
Water thoroughly to help the roots get established. Then water as the top of the soil feels dry. Do not overwater; although the plant is tropical, it is also a cactus and does not like to sit in soggy soil.
Fertilize with a balanced fertilizer made for cacti, once a month, April through September. Follow manufacturer's directions on the amount to use. Hold back fertilizer through the late fall and winter.
Repot every 2 years if grown in containers and bring it inside or place in a greenhouse when the temperature drops below 50 degrees F.