How to Grow and Care for Rhipsalidopsis
Rhipsalidopsis, also known as Crab Cactus, Bright Red Christmas Cactus, and Leaf-bearing Cactus, is an epiphytic succulent shrub in the Cactaceae family, genus Rhipsalidopsis. The plant usually forms a hanging, umbrella-like shape, with flat, fleshy, bright green stem segments similar to those of the Christmas cactus. There are bristles on the areoles, and the flowers grow from the areoles at the tips of the stem segments in a rich range of colors, making it highly ornamental. Let's take a look at how to grow Rhipsalidopsis below!
Growth Habits of Rhipsalidopsis
Rhipsalidopsis is native to Mexico, Guatemala, Honduras, Nicaragua, Suriname and Costa Rica, and is also cultivated in Guangzhou, China. It prefers a warm, humid environment, requires shade in summer and a sunny environment in winter. It grows best in loose, well-drained sandy loam soil. The optimum growth temperature is 18-22°C, and the overwintering temperature must be kept above 10°C.
Propagation Methods for Rhipsalidopsis
1. Cuttings: Rhipsalidopsis can be propagated by cuttings in March-April. Cut healthy, plump stem segments and insert them into a sand bed, keeping it moist. At a temperature of 25°C, roots form in about 40 days. When the young roots change from white to yellowish-brown, the plant can be potted up. Place some organic fertilizer at the bottom of the pot, cover it with soil, and then plant the seedling.
2. Grafting: This is usually done in spring and autumn. Common rootstocks include Hylocereus undatus, Pereskia and flat-padded cacti. If the scion remains upright and fresh green one week after grafting, it has taken successfully. Usually, 40 days after grafting, the potted seedling can be moved into the sunlight for normal care and management.
3. Sowing: Seed propagation of Rhipsalidopsis is mostly used for breeding new varieties. Plants grown from seed take 4-5 years to flower, and germination occurs about 2-3 weeks after sowing.
How to Grow Rhipsalidopsis
1. Potting soil: For Rhipsalidopsis, use 3 parts peat soil or leaf mold plus 1 part sand or perlite as potting soil. Rhipsalidopsis does not have a very developed root system, so plant it in a small pot 10-13 cm in diameter; the pot should not be too large. When potting, fill about the lower 1/4 of the pot with granular crushed brick pieces, pot shards, etc. to aid drainage and aeration. This is usually done in late spring or early summer.
2. Temperature: The suitable growing temperature for Rhipsalidopsis is 15-25°C, and the overwintering temperature should not be lower than 10°C. It has poor tolerance to high temperatures and drought. With poor management, large numbers of branches may drop off, and in severe cases the root system rots and the plant dies. The reason is that during high temperature and drought it goes dormant, and the root system's absorption capacity drops significantly.
3. Watering: Rhipsalidopsis needs plenty of water throughout its growth and flowering period, keeping the potting soil constantly moist, but avoid water accumulating in the pot. After the flowering period ends, there is a 2-3 week dormant period. Water less, only keeping the potting soil from drying out completely. After the dormant period, gradually increase the amount of watering. At first, water when about 1 cm of the soil surface has dried while the lower soil is still moist, and continue until early spring. In winter, when the indoor temperature drops below 15°C, water less, just keeping the potting soil from drying out.
4. Repotting: Rhipsalidopsis has a short dormant period after flowering, which is a suitable time for repotting. When repotting, gently shake off the old growing medium from the roots and replant with fresh growing medium. If growing it as a hanging plant, moss can be used as the potting substrate, planting the plant in a shallow pot; after the plant recovers growth, hang it indoors for display.
5. Pests and diseases: In dry air and poorly ventilated environments, Rhipsalidopsis is mainly affected by leaf spot disease and Fusarium wilt, which can be sprayed with a 1000-times dilution of 50% carbendazim wettable powder. Among insect pests, red spider mites can be controlled by spraying a 1000-times dilution of 40% dimethoate emulsifiable concentrate, or tablets can be buried directly into the potting soil.