Stand behind a gloxinia sales counter at a country fair, and in a few hours, it is evident how greatly this plant is admired. Many names will call it; gloxinia, gloxinia, tuberous begonia, and even petunia, but on one point, everyone is unanimous—it is the most beautiful plant.
However, beauty alone is not the sole criterion of a good house plant. How well the plant will grow under average conditions in the home is of equal importance. Fortunately, gloxinias perform very well if a few basic needs are considered.
Basic Needs For Gloxinia Before Flowering
Planting
Start from either plants or tubers. The newer hybrid varieties are most desirable as they produce the largest flowers in a great variety of colors.
Pot tuber or plant in a 4″ or 5″-inch pot. The tuber should be placed round side down and covered with about ½” inch of soil.
Light
A well-lighted sunny window is essential to good growth. The effect of insufficient light is easily shown by tall, lanky growth.
This may be particularly noticeable on plants grown during winter but less apparent on plants grown during spring or summer.
If leaves receive too much sun, they will turn yellow.
Humidity
Provide humidity by standing pots on trays of moist sand, vermiculite, or white chicken grits; trays of water on radiators or commercial humidifiers.
Almost all house plants benefit from increased humidity. Dry, hot rooms often cause the flower buds of gloxinia to “blast”—that is, they turn black and fail to open.
Other environmental factors may also be involved in bud blast, but low humidity is the primary cause.
Temperature
A day temperature of 70° degrees Fahrenheit and a night temperature between 62° to 65° degrees Fahrenheit is satisfactory.
Higher night temperatures produce spindly growth.
Soil
Use soil with a high humus content-3 parts loam, 2 parts peat moss, 1 part sand. A heavy, poorly drained soil is not satisfactory for gloxinias.
Fertilizer
Plants will benefit from monthly applications of liquid fertilizer. After buds have set, stop applications.
Watering
Water with lukewarm water when surface soil feels dry to the touch. Keep soil evenly moist—never soggy wet, or desert dry.
Gloxinia Care After Flowering
After all, as the flowers fade, stop watering the plant. The leaves will gradually turn yellow, and the top may be twisted off from the tuber.
Store tuber in a cool, frost-free location until about January, when it can be started to grow again.
During storage, the tuber may be left in a pot of soil. Some growers find that tubers keep better if taken out of the soil and enclosed in a plastic bag.
Insects and Diseases
Diseases are seldom troublesome. The insect thrips can cause buds to blast and flower petals to be streaked. Spraying plants at regular intervals will usually give control.