It is to be remembered that winter is naturally the season of rest for plants. All plants require to lie dormant during some portion of the year. You cannot cheat them out of it. If they are pushed the whole year, they become exhausted and worthless. Here lies the most common error of plant-keepers. If you mean to have roses, blooming geraniums, etc., in winter, you must, artificially, change their season of rest. Plants which flower in summer must rest in winter; those which are to flower in winter, must rest either in summer or autumn. It is not, usually, worth while to take into the house for flowering purposes, any shrub which has been in full bloom during the summer or autumn. Select and pot the wished for flowers during summer; place them in a shaded position facing the north, give them very little water, and then keep them quiet. Their energies will thus be saved for winter. When taken into the house, the four essential points of attention are light, moisture, temperature, and cleanliness.

1. Light. The functions of the leaves cannot be healthfully carried on without light. If there be too little, the sap is imperfectly elaborated, and returns from the leaves to the body in a crude, undigested state. The growth will be coarse, watery, and brittle; and that ripeness which must precede flowers and fruit cannot be attained. The sprawling, spindling, white-colored, long-jointed, plants, of which some persons are unwisely proud, are, often, the result of too little light and too much water. The pots should be turned around every day, unless when the light strikes down from above, or from windows on each side; otherwise, they will grow out of shape by bending toward the light.

2. Moisture. Different species of plants require different quantities of water. What are termed aquatics, of which the Calla aethiopica, is a specimen, require great abundance of it. Yet it should be often changed even in the case of aquatics. But roses, geraniums, Ac., and the common house plants require the soil to be moist, rather than wet. As a general rule it may be said that every pot should have one-sixth part of its depth filled with coarse pebbles, as a drainage, before the plants are potted. This gives all superfluous moisture a free passage out. Plants should be watered by examination and not by time. They require various quantities of moisture, according to their activity, and the period of their growth. Let the earth he well stirred, and if it is becoming dry oil the inside, give water. Never water by dribblets - a spoonful to-day, another to-morrow. In this way the outside will become bound, and the inside remain dry. Give a copious watering, so that the whole ball shall be soaked; then let it drain off, and that which comes into the saucer be poured off. But, in whatever way one prefers to give water, the thing to be gained is, a full supply of moisture to every part of the roots, and yet not so much as to have it stand about them.

Manure-water may be employed with great benefit every second or third watering. For this purpose we have never found anything equal in value to guano. Besides water to the root, plants are almost as much benefitted by water on the leaf - but of this we shall speak under the head of cleanliness,

3. Temperature. Sudden and violent changes of temperature are almost as trying to plants as to animals and men. At the same time, a moderate change of temperature is very desirable. Thus, in nature, there is a marked and uniform variation at night from the temperature of the day. At night, the room should be gradually lowered in temperature to from 45° to 50°; while through the day it ranges from 55° to 709. Too much, and too sudden heat will destroy tender leaves almost as surely as frost. It should also be remembered that the leaves of plants are constantly exhaling moisture during the day. If in too warm an atmosphere, or in one which is too dry, this perspiration becomes excessive and weakens the plant. If the room be stove-heated, a basin of water should be put on the stove to supply moisture to the air by evaporation. Sprinkling the leaves, a kind of artificial dew, is also beneficial, on this account. The air should be changed as often as possible. Every warm and sunny day should be improved to let in fresh air upon these vegetable breathers.

4. Cleanliness. This is an important element of health as well as of beauty, Animal uncleanliness is first to be removed. If ground-worms have been incorporated with the dirt, give a dose or two of lime-water to the soil. Next aphides or green-lice will appear upon the leaves and stems. Tobacco smoke will soon stupefy them and cause them to tumble upon the shelves or surface of the soil, whence they are to be carefully brushed, or crushed. If one has but a few plants, put them in a group upon the floor; put four chairs around them and cover with an old blanket, forming a sort of tent. Set a dish of coals within, and throw on a handful of tobacco leaves. Fifteen minutes smoking will destroy any decent aphis.

If a larger collection is on hand, let the dish or dishes be placed under the stands. When the destruction is completed, let the parlor be well ventilated, unless, fair lady, you have an inveterate smoker for a husband; in which case you may have become used to the nuisance. The insects which infest large collections in green-houses, are fully treated of in horticultural books of directions.

Dust will settle every day upon the leaves, and choke up the perspiring pores. The leaves should be kept free by gentle wiping, or by washing. H. W. B.