Fig. 15. Mr. Wm. Wilson's Mushroom Beds.
Drip from the Benches.—This must be prevented from the beds above, else it will soak or chill, and in a large measure kill the spawn. I have seen many examples of this evil. The beds would be full of drip holes all over their surface, and although a good many mushrooms here and there about the bed might perfect themselves, multitudes only reach the pin-head condition—or possibly the size of peas—and then fogg off in patches. It is not one or two little mushrooms in a clump that fogg off, but where one foggs off all of the little ones in that patch go, for it is not a disease of the individual mushroom, but of the mycelium or mushroom plant that runs in the bed, and when this is injured or killed all the little mushrooms arising from this particular patch of plant are robbed of sustenance and must perish.
In greenhouses where the benches are occupied with roses, carnations, bouvardias, violets, or lettuces, "planted out," as commercial florists and gardeners generally grow them, there is very little drip, because while the plants on these benches are freely watered, the soil is never soaked enough for the water to drain from it in dripping streamlets, as is continually the case in greenhouses where potted plants are grown on the stages. Under these "planted out" benches, if care is exercised, mushrooms can be grown in open beds; in fact, it is about the best place and condition for them in a greenhouse.
Fig. 16. Mushroom Bed built flat upon the Ground.
With stages occupied by plants in pots provision needs to be made to ward off the drip from the mushroom beds, by erecting over, and conveniently high above them, a light wooden framework, on which rest light wooden frames covered with oiled paper, oiled muslin, or plant-protecting cloth. In fact, three light wooden strips run over the bed, as shown in [Fig. 12], or three strings of stout cord or wire run in the same manner will answer for small beds, and act as a support for the oiled muslin or plant-protecting cloth. Building paper is sometimes used for the same purpose. Mr. J. G. Gardner uses ordinary hotbed frames and sashes, as described in a previous chapter. Light wooden shutters—made of one-half inch or five-eighths inch pine—may be used for the same end, and will last for many years.
Fig. 17. Ridged Mushroom Bed.