Answer: The mushrooms are growing because there's an underground food source. Decaying organic matter, dead roots, even decomposing compost, bark or potting soil. The mushrooms are harmless to your plants or to your soil and if you pick them out of the bed they won't sprinkle spores (reproductive organs) onto the soil. They are quite common and nothing to be concerned about. It just means there's lots of organic matter in your soil.
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