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.
Many persons are either deterred from, or misled in, growing plants in living-rooms by reading the lugubrious nonsense written about the danger of keeping plants in such situations after nightfall, or in perusing the mystified directions given from time to time for their cultivation under the head of "Window" or Indoor Gardening." Such instructions, for the most part, consists of nostrums, secrets, and tricks which are not only pernicious, but silly, and tend to puzzle and perplex the inexperienced, by creating a belief that there is much more art in growing plants in such situations than there really is.
But as the former of such statements may with propriety be placed in the category of absurdities, so may the latter instructions be transferred to that of twaddle; for the principal cause why plants in living-rooms do not thrive so well as those which are kept in plant structures, is chiefly owing to the extreme dryness of the air in sitting-rooms, and consequently their being subjected to a constant drain upon the moisture in their leaves and the soil in the pots - the leaves under such circumstances being deprived of their water by evaporation instead of by perspiration; and in the exercise of their absorbent functions being more or less disarranged from a deficiency of moisture in the air, for all plants are more or less dependent upon the vapor in the atmosphere as a source for their healthy development.
Much, however, depends also upon the suitableness of the plants selected for the purpose, and the regular attention given to them, especially during the winter months; for it is an unquestionable fact, that plants in sitting-rooms require greater care and attention, and suffer more from neglect during the dull months, from November to February, than at any other period of the year. Therefore the first thing to do in cultivating plants in living-rooms is to determine what are the most suitable kinds for such a situation; and the more select they are, according to habit and culture, the easier will be their treatment. Plants of low and humble growth should always be kept in the front, and close to the glass, while the larger growing ones may be elevated behind; and in order to favor in the greatest degree possible the harmonious growth of the plants, and obtain a uniform development of the branches and leaves, the position should be capable of admitting light as much as possible on all sides; and the best and only general rule that can be adopted is to keep those plants not in a growing state rather dry, for plants kept in sitting-rooms generally are over-watered; and it is not an uncommon thing to see plants flourish - ing in the window of a dwelling under the care of an uninitiated individual, while those under the charge of others, in adjoining houses, only linger out a miserable existence, and which frequently is occasioned by the plants being kept standing in pans, into which the water is poured when the plants are supposed to require watering; whereas, whenever water is given, it should be gently poured on the top of the earth, in the pot.
But as it is indispensable to have pans under the pots in sitting-rooms, small pans should be turned upside down within them, upon which to place the plants, and this precaution will prevent such water as may percolate through the soil from again reaching the pot in which the plant is growing; and all cultivators of window plants will find it by far the safest plan to give too little rather than too much water during the winter time, for the plants themselves will give notice when they are in much want of water by their leaves beginning to droop, while the effect of over-watering is oftentimes not discovered till the health of the plant has been seriously affected; therefore attention to this point is one of the most important in window gardening. It is, however, impossible to say how often plants should be watered, or how much at a time should be given them, as the same plant would require more or less according to circumstances; that is, in regard to the temperature of the room, and the degree of activity with which the plant may happen to be growing at the time.
It must also be observed that the temperature of the water used in watering the plants should be at least equal to that of the room, and when the plants begin to grow in the spring, increase the quantity with growth and sun's power, keeping the soil at all times in a medium state of moisture. Many cultivators are quite unconscious of the injury plants receive by a sudden change from that state in which they have been long kept to one of an opposite tendency - such as from drought to a bountiful supply of moisture, or from dark to light, such as placing plants out in the sun without their being first gradually inured to the light and air. Again, in winter, plants are frequently kept in too warm a part of the sitting-room, for they need not be removed from the window during frost, unless it be very severe, and then being placed on the floor near the middle of the room and covered with a piece of baize will suffice, as they will be safe where water placed beside them merely begins to freeze. Camellias, and similar hard - wooded and stiff-leaved plants, will even bear the soil in the pots being a little frozen; and frequently the cause of camellias losing their blossom-buds is from their being kept in too warm a part of the sitting-room in severe weather, and consequently in too dry an atmosphere.
Finally, you must never let plants suffer from neglect. Many persons let them dwindle or die by forgetting to water them at the proper time, or shelter them from excessive sun-heat and frost. Again, without training and pruning, nothing is brought to the highest state of perfection to which it is capable, for cultivation is necessary in order to exhibit the good to which every earthly nature is susceptible. Therefore stopping and training must be attended to during the growing season, as well as repotting in the spring. - Floral World.