DecorativeHouseplants

How To Grow Starfish Cactus?

starfish cactus

Starfish Cactus, Stapelia grandiflora, is native to South Africa. This easy-care plant is perfect for beginners or lazy people craving more plants in their living space.

This variety has the biggest starfish-shaped flowers in its family. Another common name for this plant would be the Carrion Flower, this name comes from the smell of rotting meat that the flower emits.

This smell is needed to attract flies as pollinators. The star-shaped flower can grow to be fourteen inches (35 cm) wide. The plant is not a cactus but is a succulent. The plant is thickly skinned and resembles carrion flesh. The flowers are usually five-petaled and are usually red and brown accompanied by a couple of other colors. 

How To Grow?

Unlike its many cousins, this cactus needs constant moisture. Another essential thing to remember is that they love crowded roots, so we suggest you buy a four to six-inch (10 to 15 cm) pot. If you’re growing your cactus indoors, provide the plant with temperatures around 70 degrees Fahrenheit (21 degrees Celsius).

Smelly

This plant has flowers that emit a smell of rotting meat. 

To make sure the blooming of the cactus flowers, provide the plant with a steady temperature of around 50 degrees Fahrenheit (10 degrees Celsius), otherwise, the cactus will not bless you with its flowers. You can grow the Starfish Cactus outdoors in the USDA Hardiness Zones 9 to 10. 

starfish cactus flower
Starfish cactus flower Source: Larry Wentzel

Light

This plant can thrive in a variety of light conditions. The best conditions, light-wise, would be full to partial sun. A good way to fulfill its light needs is by providing the plant with morning light, protecting it from the harsh midday light at the same time.

Time-wise, this plant would need about six to eight hours of light a day. If you discover your cactus looking yellow or even white and mushy it has gotten sunburned. If the white color and soft state of the plant have arrived there is nothing you can do, because this means the demise of your Starfish Cactus. 

Watering

What makes this plant great for beginners is its lack of need for water. This easy-care plant only requires watering every other week. If you plan on growing your Starfish Cactus in clay you can water it once every four weeks.

You can also grow your Starfish in sandy soil it should be watered once every two weeks. Let the soil dry out in between watering, and water very little in the winter. Avoid overwatering at all costs.

Also, remember to never spray or dip your Starfish Cactus with water. You should water the plant until water runs out of the draining holes of the pot and then wait ten minutes, after that remove any of the access water. 

Soil & Fertilizer

The best soil for your Starfish Cactus would be a well-draining potting soil with coarse sand and perlite. You can also use premixed succulent soil from the center of your garden.

To protect the roots from sitting in water when growing them in a pot you can add a one-inch (2.5 cm) layer of small gravel to the bottom of the pot. The soil should have a pH level of 6.0 to 7.8, meaning slightly acidic to slightly alkaline. 

You should fertilize your Starfish Cactus once every three weeks, but only in the spring or fall. Use an all-purpose houseplant fertilizer diluted with water. If you fertilize the plant too much and too often the plant will slowly fade away. 

starfish cactus flowering
Starfish cactus flowering Source: Tara Severns

Pruning

Pruning should be done in the fall. Pruning can be done to encourage new growth. Use clean sharp shears, scissors, or a knife. Cut back its leaves or old branches. Usually pruning is not needed with succulents other than removing diseased parts of the plant. 

Propagation

You can propagate this plant by using its seeds:

  1. Collect the seeds from the flower that has opened up.
  2. Plant the seeds, near the surface, not too deep into the proper soil, mentioned above.
  3. Make sure to keep the soil moist until germination occurs.
  4. Once the seedlings have grown a few inches tall, plant them separately.
  5. You can also propagate the Starfish Cactus from a cutting: 
  6. Cut or snap off a mature stem.
  7. If cutting, make sure to use clean and sharp shears or scissors.
  8. Let the cutting air dry under sunlight for several days. 
  9. Letting it dry out will allow the cut end callous over, making sure not too much water can enter the plant when planted.
  10. Finally plant the cutting into the proper soil, mentioned above.
  11. Care for the plant as usual.

Repotting

You should repot your Starfish Cactus every two to three years. You should also repot your plant when the plant has outgrown its current pot. Make sure to be careful when removing the plant from its former pot, remove any old soil and repot it into a pot slightly bigger. 

Diseases

The most common diseases you might come across when caring for this plant might include root rot, powdery mildew, and other fungal diseases. If a disease is spotted you should remove any diseased parts of the plant and repot the plant into fresh soil and a new clean pot. 

Pests

Most common pests you might encounter whilst caring for this plant include mealybugs, mites, aphids, and whiteflies. These pests can cause serious damage to your plant and might be the cause of the plant losing its stems and branches.

Keep an eye on your plant to discover the pests early for easy removal. The best treatment for such pests would be to use an insecticidal soap or to use horticultural oil. 

Other Types of Starfish Cactus

There are three similar plants to Starfish Cactus.

  • Stapelia Variegata – a popular succulent with four angled toothed stems.
  • Stapelia Hirsuta – an attractive succulent that can grow to be eight inches (20 cm) tall and forms diffuse mats up to 20 inches (50 cm) in diameter.
  • Stapelia Gigantea – aka Carrion flower, is a spine-free succulent, the flowers of this succulent are fringed with 0.3 inch (1 cm) long hairs. 

Conclusion

This easy-care plant is perfect for beginners looking for a cool-looking plant to decorate their living space or garden. They don’t require much time nor are they fussy about their placement regarding the sun. If you forget to water then they will be fine until you remember again. Although this species has a wide range it is mostly locally very rare and isn’t very common anywhere yet.

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