This section is from the book "The Florists' Manual", by William Scott. Also available from Amazon: The Florist's Manual.
Caladium esculentum is an important plant with the florist and it enters largely into his spring business. Every one knows this caladium and some of our customers know it by the descriptive and artistic name of elephant's ears.
They are multiplied by the small tubers that are always found on the large ones, but at the low cost of a tuber the size of a base ball (and that is amply large enough) it will never pay a florist to grow his own bulbs. You cannot begin to raise them as cheaply as you can buy them from the man who grows an acre. If you have any plants on your own place and wish to save them, cut the stalk off a foot above the 'ground' after the first frost, dig up, shake off all the soil and lay them on the ground under a rose house bench. I have found the temperature and humidity of a rose house just right providing the ground is dry.
When we receive the bulbs in the spring we cut out all the eyes and small tubers, because we don't want them, and we cut off the remains of the old tuber close up to the new, sound one. We put them in flats three inches deep in which the bottom half is sifted decayed manure and the top half sand, pushing the bulb down till its top is little above the rim of flat and the bulbs almost touching. Give them a watering and place the flats over the hot-water pipes. You will save two or three weeks by this method over starting them in the pots on a cool bench, and will save much valuable space. We plant them in the flats in time so they will be ready to pot off just after Easter, when the pressure for space has been relieved.
When taken out of the flats they have made a growth of five or six inches and are a mass of roots. They are then potted into 5-inch pots or extra strong ones into 6-inch. You do not want them too large when bedded out, as the wind breaks them, nor too late, or your customers will be disappointed; about eighteen inches high with three leaves will do. Any kind of rich soil will do for them in pots, with water ad libitum, and a light, warm house. When you are growing your caladiums all houses are-much alike as to temperature.
To make the best effect in any position out of doors the ground should be dug deep, with plenty of manure worked in. Here is a plant that the coachman can water to his heart's content. I mentioned a bulb the size of a base ball, but that is the largest useful size. Tubers that are one and three-quarters to two inches in diameter are large enough to make fine plants for summer use.
Caladium Esculentum at St. James Park, Los Angeles, Cal.
We hear that the tubers of this cala-dium are cooked and eaten in the south. Its name implies that it is edible and its other name is Colocasia esculentum.