This section is from the book "The Gardener's Monthly And Horticulturist V22", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
As the Gloxinia is one of my favorite flowers, I was very much pleased with the practical article on their cultivation in the December number of the Gardener's Monthly. I also noticed the remarks of Mr. Fyfe on the rust to which the Gloxinia is so subject, as it has caused me a great deal of trouble and annoyance, as well as the loss of the best part of my collection. But after many experiments I was enabled last season to grow all my Gloxinias perfectly free from rust by adopting the following method. As soon as I noticed that they were commencing to grow, which was about the 10th of May, I turned them out of their pots and repotted them in a mixture of one-half leaf mould, the other half consisting of loam and charcoal broken fine, in about equal proportion, taking care to give good drainage, and also to keep the top of the bulb on a level with the surface of the soil. 1 then take a cold frame and spade up the ground inside the frame. I then plunge all the pots in the frame, taking care that the tops of the pots are on a level with the ground. After the pots are all plunged, I water the ground so as to fasten the soil around the pots, then put on the sash and whitewash the glass so as to retain the moisture.
In a short time there will be a fine healthy growth, and in the course of two or three weeks, air should be given by raising up the sash at the bottom. On hot days the sash may be raised about four inches, and on cooler days about two inches, and in rainy or wet weather the sash had better be closed. The plants must be watered as often as they require it, and when the flowers commence to expand the plants can be removed to the greenhouse. If the rust should make its appearance, remove them back to the frame at once. As soon as the plants-cease flowering, they can be brought back to the frame, and the amount of water given should be gradually decreased. On the approach of cold weather, the plants can be brought into the greenhouse and placed under the stage or any place where the thermometer ranges about 50°. The pots containing the bulbs must be laid on their sides, as if the soil is allowed to get wet the bulb may rot. During the growing season the plants must be looked over occasionally,, and shifted as often as neceseary, and on no account must they be allowed to become pot-bound, for if once they become pot-bound, they soon become sickly and the prey of numerous insects.
To cultivate the Gloxinia successfully it requires a warm moist atmosphere, a temperature ranging from 60" to 75°, a slight protection from the full force of the sun, and in watering give only enough to supply their wants. When the pot is filled with roots, shift into a larger size, and give air so that the plants do not become weak and drawn.
I wish it to be understood that these remarks are not intended as a criticism on Mr. Fyfe's excellent article, as he has had more experience in plant cultivation than I probably will ever have, but as one of your correspondents inquired in the June number for a remedy for the rust on Gloxinias, I thought that my experience would be of some benefit to him.