Cool Mushrooms: A Hot Topic in Horticulture

By Eva Monheim

Field trips are an integral part of the Temple University experience. These events are probably the highlight of the semester for students and faculty, especially in the horticulture field. This spring I took my Ambler Campus Food Crops class to Phillips Mushroom Farms in Kennett Square, Pennsylvania to tour the largest specialty mushroom grower in the U.S.

Jim Angelucci, General Manager of Phillips, was our guide. When he spoke you could see the twinkle of mushrooms in his eyes. The farm has been in business since 1927 and continues to lead the industry with its contributions to food safety, substrate development, cutting edge technology, and production practices.

Jim Angelucci (far right) explaining what the students are going to see in the mushroom houses.

In preparation for the tour we all donned red hair nets to prevent unwanted contamination in the mushroom houses. Before we entered the houses we were also asked to remove jewelry and other small objects that could be lost during the tour. These types of precautions developed first at Phillips Mushroom Farm have become best practice standards in the industry.

Mushrooms Are a Big Business

The farm was so large that we had to carpool from one location to another. The white, windowless production buildings were impeccable. Each of the buildings had a “headhouse” or corridor where all the controls were located for each of the rooms. Humidity, temperature, and carbon dioxide are constantly monitored for optimal growing conditions.

This industry relies on the waste from surrounding farms that would otherwise pollute the Chesapeake Bay and surrounding tributaries. The mushroom growing medium is a blend of stable bedding from horses, chicken manure, and combinations of ground corn cobs and/or wheat straw. The blend is pasteurized, inoculated with spawn seed, put into the beds, and topped with a layer of peat moss. From the time the medium is put into the beds to full growth and harvest is a nine week cycle. The spent compost that results from mushroom production is considered to be black gold for gardens.

Jim likes to call mushrooms “vegetables without chlorophyll.” He encouraged us to eat a healthy diet of them. As we walk from room to room, he shared statistics on the increase of sales for mushrooms world-wide. Over $1.2 billion are sold each year in the U.S. Pennsylvania grows the lion’s share of this at almost $500 million.

Touring the Mushroom Houses

This photo shows the three tiers of mushroom beds with another floor above with the same configuration.

Our first stop on the tour was the white mushroom (Agaricus bisporus) houses. This mushroom is native to North America and Europe. Along the walls of the hallway stacks of mushroom trays stood almost as tall as the ceiling. The mushroom beds were made of wooden slats stacked three high. As we walked Jim gave us permission to pick one button mushroom to taste. He said we would never taste anything better than a fresh mushroom. He was right. Mine tasted flowery and earthy and was deliciously sweet.

As the tour progressed, I noticed that the fragrance varied from one mushroom type to another. This room smelled earthy and fresh and the humidity level was high. I felt like I was getting the most expensive spa treatment ever. I just wanted to breathe deeply and take in the atmosphere. Jim said he always feels great after walking through the houses. Perhaps it was the medicinal traits of mushrooms made me feel so completely energized as we continued our tour.

Both brown and white mushrooms grow so fast that sometimes they will be picking eight times a day in order to keep up with the growth. Here you can see young brown mushrooms and small pin sized mushrooms. The small pins will be mature in 24 hours or less.

The second houses that we went into were the cremini, crimini, or baby Portobellomushrooms (Agaricus bisporus), the same genus and species as the white mushroom. In 1926 a Pennsylvania mushroom grower discovered the white mushroom growing on a bed of light brown mushrooms which were the norm at the time. Once the white mushrooms were introduced to consumers they became favored over the brown. The baby Portobello mushroom is considered the same form as the white mushroom until the veil breaks away from the stem. Then the mushroom is called a Portobello mushroom. When the gills are exposed the Portobello mushroom loses moisture and the flavor intensifies. This drier and more intense flavor is what makes Portobellos desirable for grilling and as a meat substitute.

Next stop was the shiitake mushroom (Lentinula edodes) houses. Shiitake grows on the deadwood of deciduous trees.

Shiitake mushrooms are growing on inoculated logs made from the red oak sawdust.

After developing the perfect formula of growth substrate in 1979, Phillips Mushroom Farms was the first in the country to grow shiitake mushrooms year round. The shiitake rooms smelled like a forest after a heavy rainstorm. Shiitake has many medicinal benefits, making this the largest selling mushroom of the exotic fungi group. It is rich in dietary vitamin D, potassium, thiamine, niacin, and selenium.

Our last stop was the houses for the king oyster mushroom (Pleurotus eryngii), the only mushroom specifically grown for its stem. The oyster mushrooms were the most colorful of the mushrooms that we saw. When sliced down the middle and grilled it can be used for a meat substitute. It is considered to be an immune booster and good for reducing cholesterol. When cooked king oyster has the texture of abalone and flavors of umami. Royal Trumpet is the trademarked name used by Phillips Mushroom Farms in marketing it here in the U.S.

A student holding a bouquet of yellow oyster mushrooms (Pleurotus citrinopileatus).

After the Tour

Our class trip to the mushroom farm was a huge success. It became one of the highpoints of the semester. Soon after, a student arranged for a grower from Smugtown Mushrooms to come talk to faculty, students, and staff at the Temple University Ambler Campus. The enthusiasm over the talk convinced me that this topic is not going away.

The takeaway from these experiences was that the mushroom industry is growing faster than the industry can keep up with the demand. As research continues in the field of mycology, I predict we will see an explosion of mushroom growing everywhere – especially to support healthier eating, improve health, and cure disease. My students will be ready for this explosion.

Meet the Author

When Eva Monheim is not in the field with her students at Temple University, she’s on the grounds of Longwood Gardens teaching woody plants and arboriculture to her Professional Gardener apprentices.  Her commitment to education is tireless and her dedication to mentor students – paramount.   Eva leads by example – professionally trained, she is a horticulturist, certified arborist, master floral designer, artist and writer.  Her articles, designs and photographs have appeared in national, regional and local magazines and she is a former columnist for The Philadelphia Inquirer.  Eva’s education in England has given her a global appreciation of garden design and environmental sensitivity.  She is an award winning artist and loves dabbling in photography with over one million images on numerous subjects.