Fig. 11. Boxed Mushroom Bed under Greenhouse Bench.
Cool greenhouses, in all cases, are better for mushrooms than hothouses. Cool houses are seldom kept at a lower temperature than 45° or 50° in winter, while hothouses run from 60° to 70° at night, with a rise of ten to twenty degrees by day, and this is too hot for mushrooms. It is a very easy matter, by means of covering with hay or boxing over and covering the boxing with hay or matting, to keep a mushroom bed in a cool house warm and free from marked changes in temperature; but it is a difficult matter to keep a mushroom bed in a hothouse cool enough and prevent sudden rises in temperature.
On Greenhouse Benches.—It sometimes happens that the beds are formed on the greenhouse benches, and the mushrooms occupy the same place that might be assigned to roses or any other planted-out crop. The beds on the benches are made one board deep, that is, eight to ten inches of short, fresh manure, and otherwise as in the case of beds anywhere else. After the beds are spawned and cased with soil, by covering them over with a layer of straw litter or hay, sudden drying out of the surface is prevented, and in order to further prevent this drying it is a good plan to sprinkle some water over the mulching every day or two, but not enough to soak through into the bed. About the time the young mushrooms commence to show themselves, remove the mulching and replace it with a covering of shutters raised another board's height above the bed, or with strong calico or plant-protecting cloth hung curtain-fashion over the beds. The accompanying illustration, Fig. 12, for which I am indebted to Henry A. Dreer, of Philadelphia, gives an excellent idea of how mushrooms may be grown and cared for on greenhouse benches. This illustration, Mr. Dreer writes: "is made from a photograph of a crop grown on the greenhouse benches at the Model Farm, by Mr. McCaffrey, gardener to J. E. Kingsley, Esq., of the Continental Hotel.... No covering of litter is used, but the requisite shading on sunny days is secured by the use of cotton cloth stretched over the top of the bed, as shown in the engraving."
Fig. 12. Mushrooms grown on Greenhouse Benches at Mr. J. E. Kingsley's Model Farm.
My principal objection to mushroom beds on greenhouse benches is their liability to frequent and marked changes of atmospheric temperature and moisture, and to drying out. In midwinter they may be all right, but as spring advances and the sun's brightness and heat increase, the susceptibility of the beds to become dry also increases.