What's the biggest mystery in the product aisle? Mushrooms! They are not a fruit nor are they a vegetable, in fact they aren’t even a plant. What are they then? Mushrooms are classified as fungi, and they don't grown like typical produce. I love to cook and eat button mushrooms, portobellos, and more exotic mushrooms like oysters, chanterelles, and porcini so was curious to know more. I'd heard that mushrooms grow vertically and the process was sustainable, but I didn’t know much else. Curious to learn more, I headed to the source, Kennett Square, Pennsylvania -- also know as the 'Mushroom Capital of the World.'
One of the large producers in Kennett Square, To-Jo Mushrooms, offered to show me their mushroom farm. Unexpectedly the tour started at a steamy compost heap. Despite the fact that mushrooms are the only source of vitamin D in the produce aisle, they don’t see the sunlight. They grow indoors in mushroom barns where it is dark, damp, and cool. Their food source comes from the soil they grow in, not from sunlight, so it is important to have the right nutrient mix -- the carefully made compost.
The compost is inoculated (think of this as planted) with mushroom spawn. It takes three to five weeks for the mushrooms to grow. They are picked by hand and will grow two to four times before the compost is spent and the whole process begins again with fresh compost. Spent soil is recycled and used for potting plants.
If you'd like to see mushrooms growing, check out this time-lapse video.
Portobello mushrooms are actually overgrown cremini mushrooms. The industry started producing them in the '80s, but it took awhile for them to catch on.
To wash or not to wash? That's a big question for mushroom lovers and cooks. After seeing how clean and controlled the soil mix is, I feel pretty good about just brushing the soil off commercially-grown mushrooms with a damp paper towel.
I also toured Phillips Mushroom Farms, a neighboring farm that grows a large selection of delicious specialty mushrooms including shiitake, lion's mane, and oyster. Each requires a slightly different compost mix; some are not grown in beds.
Man has not been able to domesticate some of the more exotic mushrooms like chanterelles and morels. These mushrooms are still foraged by hand (hence their hefty price tag). The guys down in Kennett Square have the hookup and can connect you with their foragers.
Me, I'm enjoying my regular button mushrooms, portobellos, and some oyster mushrooms in our delicious recipes.
Watch how to make a fabulous mushroom dish, Roasted Portobello Caprese Salad: