Provide the spores with a stable mushroom substrate. Ideal materials include wood shavings, compost, wood chips or peat moss. Place the substrate in a flower box. Procure a suitably moist log for growing mushrooms like shiitake, which grow only on logs.
Set up a good watering system, like a drip system, or use a hand sprayer to keep your mushrooms moist at all times. You can set up a simple drip system by placing a container of water above the mushrooms with a piece of string or wool going from the container into the mushroom pot.
Place the spores onto the growing medium. Ensure that the substrate is kept moist for the next 2 weeks. Place a clear plastic container over the flower box to create your own mushroom greenhouse and keep moisture and temperatures constant.
Keep the temperature constant. The mushrooms need a temperature of at least 60 degrees Fahrenheit. You can use heaters in the winter to keep the temperature constant.
Provide natural sunlight for those mushrooms that enjoy light. For those varieties that prefer the dark, use a tarp to cover your mushroom pots, or place the mushrooms in a cupboard. Colonies should appear in the second week.
Retain the substrate after harvesting mushrooms, as there may be several flushes before the substrate runs out of nutrients.