Instead of assembling a tray, purchase a mushroom-growing kit from a gardening store or online. It includes all the components you need for growing mushrooms.
The manure mixed in is dried, so it shouldn’t stink up your house. However, you may try other organic compost products in place of manure-based compost.
If you chose to grow your portobellos indoors, sterilizing the soil likely won’t be necessary. You can still do it if you wish to ensure that your mushrooms grow big and healthy.
A dark area, such as in the shade of a tree, also helps, but it’s most important to get the temperature right. You can monitor the soil by placing a soil thermometer in the bed. Mushrooms do well in water, so rain falling on your planting bed is okay.
First, remove the plastic and cardboard if you used it to sterilize the soil.
If you’re growing outdoors, increase misting to twice a day to ensure the bed doesn’t dry out.
You may see white streaks in the soil, which means the mushrooms are taking root. Leave the newspaper in place and continue misting for another week.
Harvesting the mushrooms early means you’ll be eating brown criminis instead of portobellos. Wait until the edges of the caps are flat instead of curled.
