Overview
Pilosocereus robinii (Lem.) Byles & Rowley var. deeringii (Small) Kartesz & Gandhi is a species of cactus native to Florida, United States, and the Caribbean. It is also known by its common names such as Deering's cactus, Florida cactus, and Robin's cactus.Appearance
Deering's cactus grows as a tall columnar cactus, reaching a height of 15 meters in the wild. The stems are typically light green and covered in woolly, whitish hairs that are up to 3 cm long, which give it a fuzzy appearance. The stems also have numerous ribs, with areoles spaced up to 4 cm apart. Additionally, yellow-brown, needle-formed spines, grow from the areoles, and are up to 3 cm in length.Uses
Deering's cactus is often grown as an ornamental plant in botanical gardens, as well as in private collections. The fruit of the plant is sometimes eaten, and the plant has been traditionally used in herbal medicine for its diuretic and laxative effects. In summary, Pilosocereus robinii (Lem.) Byles & Rowley var. deeringii (Small) Kartesz & Gandhi is a tall, columnar cactus covered in white hairs and needle-shaped spines. It is native to Florida and the Caribbean and has been used for ornamental, medicinal, and edible purposes.Light Requirements
Pilosocereus robinii var. deeringii requires full sun exposure for proper growth. The plant does best when it receives at least 6 hours of sunlight per day. When grown in shaded areas, the plant tends to become thin, elongated, and leggy.
Temperature Requirements
The plant is native to tropical and subtropical regions, so it requires warm temperatures to thrive. Ideally, the temperature range should be between 60 to 85 degrees Fahrenheit. It is important to avoid temperature fluctuations that could damage the plant.
Soil Requirements
Pilosocereus robinii var. deeringii prefers well-draining soil that is slightly acidic. The soil should be fertile and nutrient-rich to promote healthy growth. A recommended soil mix could include sandy loam and perlite to ensure good drainage. The plant is tolerant of drought but will appreciate occasional watering to maintain a healthy appearance.
Cultivation
Pilosocereus robinii var. deeringii is a slow-growing cactus that is native to southern Florida and the Caribbean islands. It is a tropical plant that requires warm temperatures to thrive, so it is best cultivated in USDA plant hardiness zones 9b to 11.
The plant prefers full sun and should be grown in a spot that receives at least six hours of direct sunlight per day. It can be grown indoors in a bright location, such as a south-facing window.
The soil should be well-draining and slightly acidic. A sandy or rocky cactus mix with added perlite or pumice is ideal for growing Pilosocereus robinii var. deeringii.
Watering Needs
This species of cactus is drought-tolerant and can often survive with rainfall alone. It is important to avoid overwatering, as Pilosocereus robinii var. deeringii is susceptible to root rot.
Water the plant deeply and then allow the soil to dry out before watering it again. During the winter, reduce watering frequency even further.
Fertilization
Pilosocereus robinii var. deeringii does not require frequent fertilization, but it will benefit from a slow-release, low-nitrogen fertilizer every six months during the growing season (spring and summer).
During the winter, do not fertilize the plant as it enters a dormant period.
Pruning
In general, Pilosocereus robinii var. deeringii requires very little pruning. However, if the cactus becomes too tall or leggy, it can be pruned to encourage branching and a more compact shape.
Use a clean, sharp pair of pruning shears to remove the top of the stem. The plant will produce new growth from the cut area. Be careful when pruning, as the spines on the cactus can be sharp and painful.
Propagation of Pilosocereus robinii var. deeringii
Pilosocereus robinii var. deeringii can be propagated by several methods, including seed germination and stem cutting.
Seed Germination
Propagation of Pilosocereus robinii var. deeringii from seeds requires careful preparation and attention to detail. The seeds should be cleaned and soaked in water before planting. It is important to use a well-draining soil mix and a container with adequate drainage holes. The seeds should be planted at a depth of approximately 1 cm and kept moist. Depending on the conditions, the seeds may take several weeks or months to germinate.
Stem Cutting
Propagation of Pilosocereus robinii var. deeringii from stem cuttings is a faster method than seed germination. The stem cutting should be taken from a healthy plant and allowed to dry for a few days. It can then be planted in a well-draining soil mix and kept moist. It is important to protect the cutting from direct sunlight and excessive moisture. The cutting should develop roots within a few weeks, and new growth will appear shortly thereafter.
Overall, Pilosocereus robinii var. deeringii is a relatively easy plant to propagate, with both seed germination and stem cutting methods yielding successful results.
Disease Management
Pilosocereus robinii var. deeringii is generally resistant to most diseases and can survive occasional insect infestations. However, the plant can be susceptible to some fungal and bacterial diseases under certain conditions.
One of the most common diseases affecting Pilosocereus robinii var. deeringii is root rot caused by the fungus Phytophthora. Overwatering, poor drainage, and damp soil conditions can lead to the buildup of this pathogen in the soil, which ultimately affects the plant’s roots. To manage root rot, it is important to ensure proper drainage of the soil, use well-draining soil, and avoid overwatering. In severe cases, infected parts of the plant should be removed and destroyed.
Bacterial soft rot is another disease that can affect the plant. This is characterized by water-soaked lesions that appear on the stem, followed by a soft, mushy decay of the affected tissues. To control this, it is best to avoid damaging the plant’s stem or roots as this can provide an entry point for the bacteria. Infected plant parts should be removed and destroyed, and proper sanitation practices put in place.
Pest Management
Pests can pose a significant threat to the health and growth of Pilosocereus robinii var. deeringii. Some pests can cause damage to the plant’s stem, leaves, and roots, leading to reduced plant vigor and eventual death.
The most common pests that can affect this plant include the cactus moth, spider mites, and scale insects. The cactus moth is notorious for attacking the plant’s stem and can cause extensive damage. Monitoring the plant regularly and applying insecticides when necessary can help control this pest.
Spider mites are tiny insects that feed on plant sap, causing yellowing of leaves and eventual defoliation. To control this pest, regular monitoring of the plant, keeping the area around the plant weed-free, and applying insecticidal soaps can be effective.
Scale insects can also be a problem, and they tend to cluster on the stem and leaves of the plant. Regularly inspecting the plant and physically removing scale insects using a soft-bristled brush can help control their infestation. Alternatively, applying neem oil or horticultural oils can also be effective in controlling this pest.
It is essential to regularly monitor the plant for pests and diseases to catch problems early. Early detection and control can help to prevent significant damage to the plant and improve its overall health.
