Notocactus buiningii, often referred to as Parodia buiningii, is a popular and visually appealing cactus species that captivates enthusiasts with its distinctive form and vibrant blooms. Its relatively straightforward care makes it suitable for both novice and experienced growers.
Unique Characteristics
This small, globular cactus typically features a bright emerald-green body, ranging from spherical to slightly flattened, and can reach up to 8 cm in height and 12 cm in diameter. Its surface is characterized by approximately 16 sharp, pronounced ribs, from which prominent areoles emerge. The areoles bear dense, short, golden-yellow spines that create a somewhat fuzzy appearance.
The most striking feature of Notocactus buiningii is its large, showy flowers, which typically bloom from late spring through summer. These funnel-shaped blossoms are usually bright yellow, sometimes with pale yellow to shiny violet petals and bright purple stamens, and can measure up to 7 cm long and 8 cm in diameter. These diurnal flowers open during the day and close at night. Native to southern Brazil and northern Uruguay, this species thrives in rocky, mountainous regions.
Cultivation and Care
Providing the correct environment helps Notocactus buiningii flourish. This species is easy to cultivate.
Light Requirements
Notocactus buiningii thrives in bright, direct sunlight for at least six hours daily. While it enjoys full sun exposure, it benefits from some protection or light shade during the hottest parts of the day, particularly in intense summer heat, to prevent sunburn. Consistent strong light promotes compact growth and abundant flowering.
Watering Practices
Proper watering is essential to prevent root rot, a common issue for cacti. During the active growing season in spring and summer, water thoroughly only after the soil has completely dried out. In winter, when the plant enters dormancy, significantly reduce watering, providing water sparingly or only when the roots appear to be drying out to avoid complete desiccation.
Soil Preferences
A well-draining, gritty cactus mix is necessary for this plant’s health. The soil should incorporate components like pumice, perlite, clay, loam, or coarse sand to facilitate rapid drainage and prevent moisture retention around the roots. A neutral to slightly acidic pH is suitable, and extra grit can be added to the mix.
Temperature and Humidity
Notocactus buiningii prefers warm conditions and does not tolerate temperatures below 6°C (43°F), necessitating indoor placement during colder periods. While it can tolerate light frost for short durations, consistent cold and wet conditions can lead to root loss. Typical household humidity levels are acceptable for this species.
Fertilization
During the growing season, from spring to summer, fertilize Notocactus buiningii approximately once a month. Use a diluted, specific fertilizer formulated for succulents or cacti. Cease fertilization entirely during the winter dormancy period.
Repotting and Propagation
Repotting helps maintain plant vigor, while propagation allows for new plants. When the plant becomes root-bound or the pot is too small, typically every two to three years, repotting is appropriate.
Choose a pot only slightly larger, about 2 cm wider, than the current one, ensuring it has drainage holes. Repotting should occur early in the growing season using fresh, well-draining cactus soil. After repotting, wait a few days before watering to allow any damaged roots to heal and prevent rot.
Propagation of Notocactus buiningii is primarily achieved through seeds, as the plant seldom produces offsets. Seeds should be sown in sandy loam soil, kept moist, and maintained at a temperature around 14°C (57°F) for germination. Cuttings can also be used, taken in spring, allowed to callus, and then placed in a sandy mix.
Common Problems and Solutions
Despite its ease of care, Notocactus buiningii can encounter a few common issues. Overwatering is a frequent problem, leading to root rot, which manifests as mushy stems or a general decline in plant health. Adhering to the “soak and dry” watering method helps prevent this.
Insufficient light can cause etiolation, where the plant stretches and becomes pale due to a lack of adequate sunlight. Moving the cactus to a brighter location, ideally with direct sun exposure for several hours daily, will help correct this. Pests such as mealybugs and spider mites can also affect Notocactus buiningii. These are controlled by washing them off with a gentle stream of water or treating the plant with insecticidal soap.