Origin:
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson, commonly known as Graham's cholla, is a species of cactus in the Opuntia genus. The plant is native to the southwestern parts of the United States and northwestern Mexico. It can be found in the Sonoran and Chihuahuan deserts.
Common Names:
Graham's cholla is known by a few other names including Graham's tree cholla, Staghorn cholla, Club cholla, and Grape cholla. Its scientific name is derived from Charles Christopher Parry, an American botanist, and explorer, and John Milton Bigelow, an American physician, and botanist.
Uses:
Graham's cholla has several traditional uses. Native American tribes use the plant as a food source and medicinal plant. The young flower buds and fruits of the cactus were consumed raw or cooked. The fruit is sweet and juicy, and it can be used to make jellies and candies. The plant also has medicinal properties that can be used to treat various ailments such as sore throat, diarrhea, and skin abrasions. In modern times, the plant is used as an ornamental plant in gardens and landscapes.
General Appearance:
Graham's cholla is a small, bushy cactus that grows up to 3 feet tall and 5 feet wide. The stems are green in color, and they have branches that grow in a tree-like manner. The branches have numerous spines that are about 1 inch long. The flowers are yellow or red in color, and they bloom in the spring and summer. The fruit is edible and has a reddish-purple color when ripe. The plant prefers to grow in sandy or rocky soils in full sun or partial shade.
Light requirements
The Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson plant requires full sun exposure to grow and thrive. It can tolerate partial shade, but it may not bloom or produce fruit in such conditions.
Temperature requirements
The plant is native to the southwestern United States, which has a hot and dry desert climate. Therefore, it prefers warm temperatures and can tolerate high temperatures up to 100°F (38°C).
However, the plant can also tolerate freezing temperatures down to about 5-10°F (-15 to -12°C) if the soil is well-drained and dry. Therefore, it is a great option for gardeners in areas with extreme temperature fluctuations.
Soil requirements
The Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson plant prefers well-draining, sandy or gravelly soils. It can tolerate a range of soil pH levels, but slightly acidic to neutral soils are ideal.
Additionally, the plant is adapted to grow in arid regions and does not require frequent watering. In fact, overwatering can cause root rot, so it is important to allow the soil to dry out completely between waterings.
Cultivation
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson is a hardy cactus variety that can withstand temperatures as low as -10 degrees Fahrenheit. It thrives in well-draining soil and can grow in a range of soil types. The plant should be placed in a location that receives full sun, at least six hours per day.Watering Needs
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson is a drought-tolerant plant, which means it does not need much water. Water the plant sparingly during the growing season, only when the soil has completely dried out. During the winter months, reduce the watering to once every 4-6 weeks.Fertilization
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson does not require frequent fertilization. However, applying a balanced fertilizer in the spring can help promote growth. Use a fertilizer that is low in nitrogen and high in phosphorus and potassium.Pruning
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson does not require frequent pruning. However, it's important to remove any dead or damaged pads regularly. Pruning should be done during the winter months, when the plant is dormant. Wear thick gloves to avoid the cactus spines.Propagation of Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson, commonly known as Graham's cholla, can be propagated by various methods. The two primary ways are through seeds and stem cuttings.
Propagation via Seeds
Seeds of Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson can be sown during spring or early summer in a well-draining soil mix consisting of equal parts of sand and peat moss. Lightly cover the seeds with soil and water lightly. The ideal temperature for seed germination is between 70 to 75°F (21 to 24°C). Ensure that the soil is kept slightly moist, but not waterlogged, during the germination process. After germination, the seedlings should be transplanted to individual pots, where they should be kept in a bright and warm location with indirect sunlight. Once established, they can be planted outdoors or in larger containers.
Propagation via Stem Cuttings
Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson can also be propagated through stem cuttings. Using a sharp, sterilized knife, cut a healthy stem approximately 4-6 inches (10-15 cm) long from the parent plant. Allow the cuttings to dry for a couple of days in a shady, warm location until the cut ends form a callus. Once the cut ends are sufficiently callused, plant the cuttings in a well-draining soil mixture in a pot. Water the cuttings sparingly until roots begin to form. It is essential to keep the soil moist but not waterlogged. Once the cuttings root, they can be transplanted into individual pots or planted directly into the ground.
Disease Management
The Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson plant is susceptible to various diseases, such as:
- Anthracnose: a fungal disease that causes small, sunken spots on the pads, which turn brownish-yellow with time. It can be prevented by ensuring good airflow, avoiding wet foliage, and removing infected pads.
- Bacterial Soft Rot: a bacterial disease that causes soft, watery rot on the pads. It can be prevented by avoiding overwatering, removing infected pads, and disinfecting tools to prevent the spread of bacteria.
- Phytophthora Root Rot: a fungal disease that causes root rot and wilting of the plant. It can be prevented by ensuring well-draining soil and avoiding overwatering.
To manage these diseases, it is essential to practice good hygiene, maintain good air circulation, and avoid overwatering the plant. Early detection and prompt action can also prevent the spread of diseases.
Pest Management
The Opuntia schottii Engelm. var. grahamii (Engelm.) L. Benson plant is also susceptible to various pests, including:
- Cochineal Scale: small, oval, pinkish-white insects that cluster on the pads. They can be controlled by physically removing them with a cotton swab dipped in alcohol or by releasing natural predators, such as ladybugs.
- Spider Mites: tiny, spider-like pests that suck sap from the plant, causing stippled leaves. They can be prevented by spritzing the plant with a forceful stream of water or by using insecticidal soap.
- Opuntia Beetle: a beetle that feeds on the pads, causing defoliation and stunted growth. They can be prevented by using insecticidal soap or neem oil.
Regular inspection and early detection can help prevent the spread of pests. Using natural predators, such as ladybugs, can also help control pest populations. It is essential to use pest management products as directed to prevent harm to the plant and the environment.
