How do you prevent mushrooms from growing in my garden?

== == Mushrooms are a fungus, or more accurately the fruiting growth of a fungus, the actual mycelium are underground. A general purpose fungicide will help but most mushrooms are beneficial in that they break down nutrients in the soil so that they are more readily available to the plants. One treatment is to apply 1lb of nitrogen per 1000 sq ft, break up the soil so that it drains better, and remove any wood product that is not fully decomposed ( that's what the fungi feed on ) try to allow the area to dry out between watering.