Those who have had experience know that no cultivated fruit will grow under glass with as little care and expense, and fruit as bountifully, as some varieties of the strawberry. The low structure with the vines only two or three feet from the glass gives the best results. A few years ago the system of growing bright-colored and good berries in this way for winter marketing at fancy prices became quite a large business. But the extensive growing of the strawberry on the Gulf coast and delivering them North at moderate prices has about confined the work to amateur growers, who derive satisfaction and pleasure, if not profit, in watching the development of strawberries in winter.
The main essentials to success are : (a) The selection of perfect-flowering varieties, as the pistillate ones will need hand pollination in the still air of the plant-room. (b) The plants should be rooted in three-inch pots the previous summer, by sinking the pots and rooting the plants starting on the runners in the pots. When well established, and the pots full of roots, keep them in an airy place until cold weather, with occasional watering. When placed under glass shift to four-inch pots. (c) A temperature of GO to 75 degrees in the day and 50 to 60 at night is favorable, and indeed any care favorable for such hardy plants as the geranium will suit the strawberry. (d) When the fruit is developing, water can be applied more liberally, and application of liquid manure at this time will give increased vigor to the plants and an increased crop of fruit.
Over a large part of the United States and Canada the strawberry is lessened in yield of perfect fruit and health and thrift of vine by direct exposure to prevailing drying winds. This is specially true in the arid States and over those west of the great inland lakes. Experiments made by Professor Green, of Minnesota, and others in the prairie States, have demonstrated that beds sheltered from dry winds, and protected from the direct rays of the sun by lath frames - as practised by pineapple growers in Florida - have given a still greater increase in size and perfection of fruit and health of foliage. In practice the lath-shading would not prove profitable, but it pays well where possible to select positions for planting sheltered by tree growth, or in other ways, from prevailing dry winds in the growing season. The same is true of the raspberry and blackberry. In nature they are found usually in sheltered and even shaded positions, and direct exposure in the interior states to raking winds not only lessens the fruit yield, but favors the development of the small fruit fungi referred to in the chapter on spraying (Chapter XII. Spraying For Insects And Fungi).