This section is from "The Horticulturist, And Journal Of Rural Art And Rural Taste", by P. Barry, A. J. Downing, J. Jay Smith, Peter B. Mead, F. W. Woodward, Henry T. Williams. Also available from Amazon: Horticulturist and Journal of Rural Art and Rural Taste.
A. P. Calder, who had been remarkably successful in forcing the Lily of the Valley, was called upon to give his method. He said that he commenced to force this flower because he found it necessary in making up work at the store. It has been considered very difficult to force/ There are two very important points - plenty of bottom heat and plenty of moisture. After the flower has formed, the plants must be kept very cool, and have no water. No water must touch the leaf or flower after the flowers have two-thirds developed. Too much water rots not only the flower stems, but the leaves. He sold 200 selected clumps to a gentleman who allowed them to get dry, and they grew only two inches high.
In answer to the inquiry as to the soil used, he said that it was not particularly prepared. He took common loam from the field. It requires a very strong bottom heat to start it; afterwards it is easily grown. He has five pipes under the bench, which give a strong bottom heat. His plants are placed in boxes. Clumps from the same box, without bottom heat, did not grow at all.
Mr. Rand, in answer to an inquiry concerning the rose-colored variety, said that he had six or eight kinds, and as far as regards flowers, the common is the best of all. The so-called rose-colored variety is a dirty pink. Some of the variegated foliaged kinds, especially the golden variegated, are valuable.
In answer to the question whether the Lily of the Valley succeeds best in the sun or shade, Mr. Calder said that out doors it grows in the sun, and indoors his best plants are in a stove house with 17 pipes, and exposed to the hottest sun.
The only soil used, other than what came on the clumps, was a little in the box and between the clumps. It is not necessary to put in soil. The object of withholding water is to keep the blooms clean and white; the smallest quantity of water spots them. He does not give them a particle of liquid manure.