The Mushroom (Agaricus campestris) is an elusive fungus. It will flourish amazingly in some places, and in others will absolutely refuse to respond to the coaxing of the cultivator.
I once knew a man whose place - it was in a suburb of London - was so alive with spawn that Mushrooms seemed to fly up everywhere, whether they were wanted or not. On the other hand, I have known plenty of people take no end of trouble to get a crop, and fail.
To take pains is, of course, a capital trait in any person's character, but it is not enough in itself, for the unhappy grower may be working in the wrong direction. No trouble will compensate for unsuitable manure, or bad spawn bricks. So important, however, are these two factors, that if they are right the rest of the business is easy.
Mushrooms will not grow in rank manure, and it is useless to try and make them. They will, however, grow in sweet manure if it is at the proper temperature. Let us ponder these things.
To make anything of a bed, two loads of manure will be wanted; half a dozen would be better. This manure should not be wet, slimy stuff out of a stockyard, but straw and horse droppings from a stable. It does not matter if it is secured in instalments, so long as they are not so small, and so far apart, as to lose all their heat as fast as they are got in. The heap should be turned five or six times to drive off noxious gases, and if it does not heat it should be sprinkled with water.
When the bed is built up, sticks should be driven into the ground 2 1/2 feet apart, and inclined at an angle which will bring them to within 6 inches of each other at the top. Build to their outline, shaking the manure well out, and treading it firmly.
Now for the spawn. I have had to handle many tons of "bricks," and those which I like the best are the ones that are delicately webbed over with a whitish film. If uniformly dark in colour I do not care for them.
The bed is ready for the spawn when the trial stick which has been driven into the bed has cooled down from a temperature at which it cannot be grasped without pain to one at which it is pleasantly warm, say 80°. Never spawn when the heat is on the up grade, or your spawn may be baked. Each brick will give eight pieces, and each piece should be wrapped in a bit of litter and thrust into the bed until it is well hidden.
Watch the bed after the spawning, and in a few days look for white threads running from the pieces of spawn. Directly they are seen, cover the bed with 1 inch thickness of good loamy soil, damp enough to bind when it is beaten down. Then cover the whole bed with straw or litter to keep in the heat. If Mushrooms do not appear in six to eight weeks, mix nitrate of soda in warm water at the rate of 1 oz. per gallon, and give the bed a good soaking.
It is easy to fail with Mushrooms by beginning at the wrong time. Those who live in the country know that Mushrooms rarely come in any quantity during the dog days. It is too dry. The Mushroom harvest comes when the sun-baked ground is moistened by the rains of September. Observing this, the gardener learns that he would act unwisely if he made up his beds at such a time - April or May - that the Mushrooms would have to make their effort to come into being at midsummer. He therefore makes a start in summer for an early autumn crop, or in winter for a spring one. The fact that some very skilful and experienced growers seem able to get a crop at all seasons of the year must not be allowed to carry too much weight.
The man who is lucky enough to possess a proper Mushroom house, or some cool, dark building that may be pressed into service, can manage with far less manure than his less fortunate brother. A depth of a foot is usually enough, and with a steady air temperature of about 55°, with humidity, darkness and cleanliness, Mushrooms will speedily come, if the other points of culture indicated are attended to.