Origin
Thelocactus bicolor (Galeotti ex Pfeiffer) Britt. & Rose var. schottii (Engelm.) Krainz, commonly known as Schott's fishhook cactus, is native to the Chihuahuan Desert and Mexico, specifically in the states of Chihuahua, Coahuila, Durango, Nuevo León, and Zacatecas.
Common Names
Thelocactus bicolor var. schottii is commonly known as Schott's fishhook cactus or desert ball cactus.
Uses
The Schott's fishhook cactus is often grown as an ornamental plant. It is popular due to its small size and attractive appearance. The plant is also used in traditional medicine in Mexico as a treatment for fever and kidney problems.
General Appearance
The Schott's fishhook cactus is spherical or cylindrical with a green-grey or blue-grey appearance. It can reach up to 10 cm in diameter and 15 cm in height. The stem has 15-20 prominent ribs that are covered in spines. The spines are reddish-brown or yellow and are curved downwards like fishhooks, which gives the plant its common name. The flowers are funnel-shaped and range in colour from yellow to pink or purple. The plant produces small, red, fleshy fruits that contain black seeds.
Light Requirements
Thelocactus bicolor var. schottii plants need plenty of sunlight to grow. They can handle full sun as long as they are not exposed to extremely high temperatures for extended periods. During the summer, provide at least six hours of direct sunlight every day. During the winter, reduce the amount of light and provide partial shade to prevent sunburn.
Temperature Requirements
These cacti prefer warm temperatures, especially during active growth periods. During the summer, the optimal temperature range is between 75ºF to 85ºF. During the winter, they prefer cooler temperatures between 50ºF to 60ºF. Protect them from frost and extreme temperature changes, which can be detrimental to their growth and health.
Soil Requirements
Thelocactus bicolor var. schottii prefers well-draining soil that is rich in organic matter. A mixture of cactus soil, sand, and perlite works best. This type of soil allows excess water to drain away from the roots, which helps to prevent root rot. Make sure to always allow the soil to dry out before watering again.
Cultivation Methods for Thelocactus Bicolor Var. Schottii
Thelocactus Bicolor Var. Schottii makes an excellent indoor and outdoor plant, as it is adapted to grow in hot, dry conditions. The plant grows best in areas that receive partial to full sun and high temperatures ranging from 70 to 90°F. It thrives in well-drained soils, and if planting indoors, make sure the pot has holes to let excessive moisture out. When planting outdoors, place the plant in a location that has good drainage, and the soil must be well-drained and aerated to prevent root rot.
Watering Needs
Thelocactus Bicolor Var. Schottii is drought-tolerant and only requires watering once every three weeks during the growing season. Overwatering can cause the plant to rot, so ensure that the soil is entirely dry before watering. During the winter months, the plant goes into dormancy, and watering should be less frequent. The rule of thumb is that the plant should be allowed to dry out entirely before watering.
Fertilization
Fertilizing Thelocactus Bicolor Var. Schottii is not necessary, but it can help the plant to grow bigger and healthier. Fertilize the plant with a low-nitrogen cactus or succulent fertilizer once every spring, at the start of the growing season. Never fertilize the plant during winter or dormancy period.
Pruning
Thelocactus Bicolor Var. Schottii rarely requires pruning, but if the plant has dead or damaged stems, use a sharp, clean pair of scissors or pruning shears to remove them. Use caution when pruning cacti, as they have small, sharp spines that can cause injury. When pruning, wear protective gloves and glasses to avoid injury.
Propagation of Thelocactus bicolor var. schottii
Thelocactus bicolor var. schottii can be propagated through different methods. Here are some of the common and effective ways to propagate this plant:
Seed propagation
One of the most common ways to propagate Thelocactus bicolor var. schottii is through seeds. Collect the seeds during the plant's flowering season, usually in the summer or fall. Sow the seeds in well-draining soil mixed with sand to increase drainage. Place the pot in bright and indirect sunlight, and keep the soil moist. The seedlings will germinate within two to four weeks.
Division
Another way to propagate Thelocactus bicolor var. schottii is through division. This method is best done in the spring or early summer. Carefully remove the offsets from the parent plant, making sure each offset has enough roots. Allow the offsets to callus for a few days before planting them in well-draining soil mixed with sand. Place the pots in bright and indirect sunlight, and water the soil once a week.
Stem cutting
Thelocactus bicolor var. schottii can also be propagated through stem cuttings. Take a stem cutting during the plant's active growth season, usually in the spring or summer. Allow the cutting to callus for a few days before planting it in well-draining soil mixed with sand. Place the pot in bright and indirect sunlight, and water the soil sparingly until the cutting develops roots.
Disease Management
Thelocactus bicolor var. schottii is a hardy plant and is relatively disease-resistant. However, it may develop the following diseases under adverse conditions:
1. Rotting
Overwatering can cause the roots to rot. So, avoid watering the plant excessively or frequently. When you observe the signs of rotting (such as discoloration of the stem, a foul smell, wobbliness, etc.), repot the plant in a fresh, well-draining soil mixture.
2. Fungal infections
Fungal infections can cause a variety of problems such as leaf spots, stem cankers, blights, etc. These infections are usually caused by overwatering or high humidity. To prevent fungal infections, ensure that the plant is located in a well-ventilated area where the soil can dry out between watering sessions. If infected, prune the affected parts and apply appropriate fungicides as per the instructions.
Pest Management
Thelocactus bicolor var. schottii is not immune to pests, and mites and mealybugs are the common pests you may encounter. Here's how to deal with them:
1. Spider mites
Spider mites are tiny mites that feed on plant sap, causing yellowing and stippling of leaves. They are often found in dry and dusty conditions. You may use a stream of water to wash off the mites or use insecticidal soap, neem oil, or horticultural oil to keep them at bay. Repeat the application per the instructions to ensure complete eradication.
2. Mealybugs
Mealybugs are tiny bugs that create sticky secretions on the plant, which attracts other insects such as ants. Use a stream of water or cotton swab soaked in rubbing alcohol to remove them. You can use insecticidal soap, neem oil, or horticultural oil, but be mindful of the concentration to prevent damage to the plant.
Regularly inspect your plant for any visible damage or infestation. In case of severe damage or infestation, you may need to dispose of the plant to prevent the spread of pests and diseases to other plants.
