The vast majority of gloxinia on the market today are hybrids of Sinningia speciosa. However, by crossing Sinningia speciosa with other plants from the Sinningia genus, such as Sinningia regina, breeders have been able to create a wonderful kaleidoscope of colors and flower forms, including striped and double flowers. Gloxinia is not especially hard to grow, and if you can grow African violets, you can be successful growing gloxinia. Outside of their hardiness zone, you can place or plant them outdoors in the spring. Although they are tuberous plants that will regrow from the underground tuber after blooming, it’s probably best to discard bloomed plants as they will never regain their original vigor. Among gloxinia enthusiasts, it’s often a goal to collect as many colors and flower shapes as possible.
Light
Gloxinia prefers partial to full shade conditions. Do not locate it in or expose it to direct sunlight ; bright, indirect light is best.
Soil
Keep soil constantly moist throughout the growing and blooming season. If you’re going to repot it after the blooming is done, reduce watering and let the leaves die, then repot into a fresh pot and begin watering again after it’s sprouted. A loose, well-draining, slightly acidic potting mix, a mix formulated for gardenias or African violets, is best.
Water
Gloxinia needs to be watered often enough so that the soil remains moist. When you water, make sure not to touch the leaves with your watering can as this can cause brown spots to form.
Temperature and Humidity
The average temperature should be 70-78 degrees Fahrenheit. Gloxinia does not like dry heat. Provide humidity, but do not directly spray its velvety leaves with water. Misting encourages fungal diseases.
Fertilizer
Fertilize during the growing season with liquid fertilizer or controlled-release fertilizer according to label instructions. Reduce fertilizer during dormancy.
Pruning
Pinch off the dead or dying leaves of your gloxinia to keep it healthy.
Propagating Gloxinia Hybrids
Gloxinia is relatively easy to propagate. You can take leaf cuttings when the plant is actively growing and sprout them in damp sand or seed-starting soil. Alternatively, you can divide the tubers during repotting and repot tuber pieces into individual pots. That said, however, most modern gloxinias are bred to produce very large flowers and will never regain their original glory after reblooming.
How to Grow Gloxinia Hybrids From Seed
Gloxinia seed is very fine and super tiny. Be careful when opening the seed packet: a small gust of wind could sweep them away in less than a second! Sprinkle seeds on potting medium, then gently spray with water. Do not cover them with soil. Keep in a warm, light location until germination occurs. Once the seedlings have two pairs of leaves, they can be transplanted into a larger pot.
Potting and Repotting Gloxinia Hybrids
When it comes to repotting, gloxinia should be left alone during the growing season. Repotting should only be performed in the late winter when last year’s growing season is done, and the leaves have died back. When you repot, put the tuber into a slightly larger pot with fresh, slightly acidic soil and resume watering. New leaves should sprout from the tuber, and the plant will continue growing until it flowers again. Flowering can happen at any time of the year.
Common Pests and Diseases
Gloxinia is sensitive to both lack of airflow, and water on its leaves. Both will encourage rot. Also, they should not be left sitting in water for any longer than necessary, as this will encourage tuber rot. On the other hand, plants that are too dry begin to experience rolled-up leaves. Gloxinia is susceptible to aphids, mealybugs, whiteflies, and scale. Remove infected plants from proximity to other houseplants and discard them. The use of sprays and insecticides will usually ruin the delicate blooms.
