Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
I love plants that are a little different. Rat tail cacti, with their dramatically draping stems, have been a fun addition to my houseplant collection.
What Is Rat Tail Cactus?
Rat tail cactus (Aporocactus flagelliformis) is a flowering cactus that is native to southern Mexico and parts of Central America. It is found in higher elevations so it prefers cooler temperatures than most tropical plants from that region. The rat tail cactus has been a popular houseplant since its introduction to Europe in the 17th century.
The plant earned its name by the way it grows. Instead of growing upwards, the thin stems drape. They look like rats' tails. In its natural environment, the plant grows along the ground or in the crotches of trees. Most gardeners grow the cacti in hanging baskets, allowing it long stems to drape from the edges of the pots.
Rat tail cactus grows best in full sun. Its stems can grow 4 – 6 feet long. They are half an inch thick and covered with short spines.
The flowers are usually red, although pink and orange are occasionally seen. The flowers grow directly from the stems. They are tubular in shape and 2 – 3 inches in length. Bloom time is spring through early summer. The dried flowers have been used medicinally by the indigenous peoples of Central America.
How to Grow Rat Tail Cactus
Most gardeners grow rat tail cactus in hanging baskets. Use a wire basket that is lined with sphagnum moss or coconut coir for good drainage. Fill it with regular potting soil. These plants grow quickly so plan on repotting your plants every year, preferably in the spring.
Most potting soils these days come with slow release fertilizer so you don’t have to worry about fertilizing your cactus. If the potting soil you are using has no slow release fertilizer or you mix your own potting mix, then you will need to fertilize regularly during the growing season. Use a liquid fertilizer formulated for houseplants. Dilute it to half strength and apply it every two weeks in the spring and summer months. Do not fertilize during the fall and winter when the plant is resting.
Rat tail cacti need full sun, so place your plant in a south- or west-facing window. Give it a sunny spot outdoors if you bring it outside during the summer.
These plants are native to higher elevations and prefer cooler temperatures. They can tolerate temperatures as high as 90⁰F, but it’s a good idea to give them some afternoon shade during heatwaves. In the spring, you can place your cacti outside when nighttime temperatures are above 40⁰F. Bring them indoors in the fall when the nighttime temperatures fall to 40⁰F.
Keep your plant well-watered during the spring and the summer months. Aim to keep the soil moist, not wet. During the fall and winter, the plants are dormant, so they require less water. Only water when the soil is dry.
How to Grow Rat Tail Cactus From Stem Cuttings
Rat tail cactus are easy to propagate from stem cuttings. Some gardeners start cuttings when their plants have outgrown their containers. Transplanting mature plants can be tricky thanks to the spines. Spring and summer when the plants are actively growing is usually the best time to take stem cuttings.
If you just want to root a single plant, take a cutting from the end of one of the stems. If you want to root multiple cuttings, you can sever a stem and cut it into 1 inch pieces.
Set your cutting or cuttings aside for about three days to callous. You want the cut end to dry out and form what looks like a callous. This protects it from disease and insects invading it while it is rooting.
Once the callous is formed, it can be placed in a container filled with moist potting soil. It helps to water the soil before you plant your cutting. Watering after you plant your cutting could result in the both the soil and the cutting washing out of the pot.
Plant your cutting very shallowly, about 1/8-inch deep. It may fall over, so you might want to add some kind of support for it until it grows roots.
Place the container in a sunny window and keep the soil moist. Roots should start to grow in about 2 – 3 weeks.
© 2020 Caren White