Window Gardening With Gloxinia
True Gloxinias, charming plants for window gardens, the home greenhouse, garden potting shed or protected shady spots outdoors in the summer, may be started from tubers, young plants, leaf cuttings or seeds.
Growing gloxinias from leaf cuttings makes pleasant window gardening. Select green, robust leaves while the plant is still in bloom or in bud. Sever the leaves as close to the main stem of the plant as possible, where the leaf-stems are hard, and insert in a mixture of sand and peat moss or vermiculite. Or if you prefer, leaf cuttings will root easily in a glass of water. In about two months well-formed tubers will appear at the base of the leaf stems.
If you root gloxinia leaves in vermiculite or in peat moss and sand, remember to water them at least once a week after the leaves die. When they show signs of sprouting, remove them to four or five inch pots of soil. Cuttings always come true to colour.
Growing gloxinias from tubers is the easiest method of all. Simply set dormant tubers on moistened sphagnum moss, partially sterilised sand, vermiculite or some commercially prepared soil mixture. Or you can plant them directly in a 4-inch pot of soil. Then set in a warm place and water slightly until growth appears. As soon as leaves spread apart, transplant to individual pots and place in an east or south window.
You may also buy young seedlings in 2″ containers. Pot these as you would tubers and they will produce blossoms in three months. This method is the easiest for the beginner.
After the first crop of blooms, cut the old growth off, leaving the last two leaves. New growth will appear and you will get another crop of blooms, not so many or large as the first, but still worthwhile. After the second crop of bloom, do not try for a third, but give the tuber a rest.
Gloxinias sometimes refuse to go dormant. They are unpredictable in that some rest a week, others three months. The bulk of the hybrids, however, require little, if any, rest. After the plant has ceased flowering, cut it back to the last two leaves and decrease the amount of water. If new shoots spring up in a week or two, the plant will not need rest and will perhaps favour you with more flowers.
Tubers can be stored in the pots in which they grow by placing them in a basement or other storage quarters where the temperature is about 50 to 55 degrees F. Sprinkle the soil with water once a week to help keep the tubers firm and plump. If some sprout, and you do not have time to plant them, it is better to remove the sprouts and, if possible, find a cooler storage place than to let them grow spindly in the dark.
The window gardener is likely to have gloxinias that are willowy if they do not have enough light. If so, give them more sunlight or boost them closer to the fluorescent lights, if you grow them that way. By placing them a few inches from the lights while they are growing, and then lowering them when they come into bloom, you can have well-shaped specimens.
A lack of diseases and pests has helped to make gloxinias popular. Tiny, black, thread-like thrips will take a devastating toll if not arrested. These leave a reddish, excrement on stems and the undersides of leaves. To eradicate use spray-type insecticide soaps made especially for house plants or neem oil.
Tuber bacteria is likely to set in and ruin dormant tubers if they arc left in a soggy, wet condition. Occasionally a gloxinia that seems to be in perfect condition, even in full bloom, will suddenly wilt, and close examination will show that black rot has enveloped the tuber and started up the stems of the plant, cutting off all food. A light, well-aerated soil, rich in organic matter, is likely to avoid this rot, but if troubled with it, cut off the leaves or top growth that is not infected. Root the salvaged portions and destroy rimed parts.
Keep Water off Buds
Spilling water on the buds and allowing it to remain inside the sepals over night is likely to rot buds. Lack of humidity is another problem. In this case set the pots on trays of moist sand and peat moss.
Not enough water, or too much, will cause buds to dry up before opening. Placing a plant which is in full bloom in hot sunshine will cause the blossoms to wilt badly and shorten their endurance. The ideal growing temperature is from 62 to 85 degrees F., and a few degrees below or above are not harmful.
Equal parts of peat moss, leaf mold, garden loam and sand make a standard growing mixture. There are packaged mixtures prepared especially for gloxinias, handy when one has but a few tubers.
For a window box or in great apartment plants with a north or northeastern exposure nothing can compare with gloxinias. For bedding in shaded, protected spots, they are excellent, and if you live in a very warm climate, where it might be hard to keep them in good condition indoors, they will luxuriate outdoors from late spring until fall.
The true species of gloxinias are always charmingly delightful. Sinningia regina and S. macrophylla (Brazillian gloxinia) sport beautiful reddish leaves, veined with silver, and rosy red on the undersides. They have darkest purple, tiny slipper flowers.
With all the hybridising going on all over the USA and in Europe as well, we are wondering what we will find in the way of gloxinias in years to come. One thing is certain – we will not only have better kinds, but also many new ones. Furthermore, there will be thousands of new enthusiasts! And who knows, gloxinias might he the most popular window gardening and greenhouse plant of the day!