Incandescent bulbs give off red rays that are beneficial to plants. Although they also give off more heat than fluores cents, they are the answer to maintaining large foliage plants, hanging baskets, and trees where natural light is not bright enough. Use standard Cool Beam (General Electric) or Cool-Lux (Sylvania) spotlights in ceramic sockets. These can be mounted on inexpensive light stands (the kind used by photographers), or in a ceiling track system. The bulbs are available in sizes from 75 to 300 watts. Smaller ones can be as close as 12 to 18 inches from the leaves, larger ones may need to be 3 or 4 feet away so that the foliage is not burned. Give plants 6 to 12 hours of illumination out of every 24. Spindly new growth indicates not enough light; increase wattage or hours of illumination. Burned foliage indicates light is too close. Wilting may be caused by light too close, or the plant may need more water.

   A home greenhouse of any size offers indescribable pleasure to an indoor gardener. Here, tropicals can be grown which may be too large or too difficult to handle in the window garden. A greenhouse gives the hybridizer, the propagator, and the ardent collector extra space for an always expanding hobby.

   A window greenhouse is a small luxury which will fit into almost any gardener's space and budget. A heated window greenhouse makes a delightful display area for such plants as begonias, geraniums, orchids, and cacti. Prefabricated models are available (pp. 301-05); otherwise, anyone looking for a small building project will find a window greenhouse easy to construct.

   These small greenhouses have glass or heavy-gauge transparent plastic on the top and three outer sides. The fourth side can be left open to the room, or it may be formed by the window of the house. In building such a greenhouse, use rot-resistant wood for the framework. In size it should not be so large that it will look ungainly. Mine, which accommodates about thirty plants in 4-inch pots, is 20 inches deep, 32 inches wide, and 22 inches high. It is situated on the east side of our house. The top slopes so rain and snow can drain off.

   Inside my window greenhouse, potted plants are set atop moistened pebbles in a galvanized tray. A thermometer and humidity combination inside the unit tells me whether the area needs added heat, ventilation, or moisture. In severely cold weather, an electric soil cable, obtainable from seed stores and mail order houses, warms the air. Vents on the top and bottom of the end panels serve to admit fresh air.