July 31, 2014

Boulder High Country Mushrooms

As I wandered around 63rd Street Farm, I was drawn to a colorfully painted shed. Two men absorbed in their activities stopped and explained that they were growing mushrooms inside the shed. I have seen mushrooms growing on the ground, logs, trees, and compost piles. Until I visited Country Gardens Farm, I had the romantic notion that expert mushroom hunters go out harvesting mushrooms from the wild, supplying supermarket shelves around the country. At Country Gardens Farm, they grow mushrooms in log towers in a shady wooded area. I hadn't considered that mushroom farmers might also grow mushrooms indoors.

Michael Heim of Boulder High Country Mushrooms explained what goes on inside the mushroom shed. It really does start with expert mushroom hunters. They collect pieces of edible and medicinal mushrooms growing in the wild. Back at the mushroom lab, they culture their harvest in malted agar.

Michael explained that the malt provides the food needed to grow into mycelium, the underground, thread-like, part of the mushroom. From there, the mycelium are cut with a sterilized knife and transferred to another growing medium. Michael showed me many jars of sterilized wheat berries growing mycelium.

In short order, the mycelium permeates the wheat berries. At this point, the mycelium may take divergent paths depending on the mushroom species being grown. Some continue to grow in a bag of sterilized wood chips, spent coffee grounds, and sawdust. Others will be placed in a bag of sterilized furniture dowels! Yes, furniture dowels. Subsequently, the dowels may be used to inoculate logs. First, drill holes in the log. Next, pound the dowels in the holes. Finally, cap with wax, to keep the critters out. Other mushroom varieties are placed in sterilized yerba mate. And some are placed in sterilized rice.

Before long, the mycelium is ready to fruit. The fruit is the part we eat. It is what we normally refer to as mushrooms. The mycelium is transferred to larger bags at this stage.

Michael Heim in front of 6 foot tall grow bags

The bags are kept in a controlled, humid environment. Once the fruit breaks through the bag, it can grow large and be picked easily.

Perhaps you noticed the repetitious use of the word sterilized in the description of this mushroom farming process. That is because good hygiene is paramount on a mushroom farm. Any contaminants to the growing media can prevent fruiting. A small operation will be dependent on preventing weed, pest, bacterial, viral, and fungal contaminants through sterilization/pasteurization and creating clean areas. A fierce focus on keeping contaminants out of the process is vital. If a small mushroom farmer is able to keep the farm clean during all stages of the process, there is no need for pesticides, herbicide, or fungicides.

Another potentially sustainable feature of mushroom farming lies in the choice of growing substrate. Many mushroom growers use organic waste from agriculture, landscaping, and food processing. Boulder High Country Mushrooms creates one growing mixture from spent coffee grounds, wood chips, and sawdust. All three are waste products from other industries.

Due to the heavy-handed use of sterilization/pasteurization at the mushroom farm, any renewable source of hot water would make the operation more sustainable. Michael mentioned this as he brought me out back to a large compost pile. I did not see the significance.

It is well known that compost piles heat up. In fact, that is one of the signs of a healthy pile. The heat indicates decomposition is going on and it kills many of the pathogens that might be present. Although decomposition is the primary purpose of most compost piles, Michael explained that the primary purpose of this pile is to pre-heat water. Decomposed compost is a secondary benefit. Jared Urchek, the owner of Boulder High Country Mushrooms, built the pile. He layered manure and wood chips. As he put down each layer, he coiled a layer of water hose. There are 1000 feet of hose buried in the pile. As water flows through the hose in the hot pile, the water heats up to about 130°F, thus providing pre-heated water for the farm. Great idea!

Here's one last thought on sustainability. Mushroom farming would be a wonderful enterprise in an urban area, where space is at a premium. Farmers can grow up to 25 pounds per square foot per year. And in a city, the farm could share space with a mushroom museum. No, I'm not really serious about that last point, but some of these specimens would make gorgeous works of art. The day I visited Boulder High Country Mushrooms, they were loading up to deliver the most spectacular oyster mushrooms I have ever laid eyes on.

Michael Heim and Jared Urchek with oyster mushroom specimens

If you live in the Boulder area and want some locally grown mushrooms, give Boulder High Country Mushrooms a call at (720)722-3512. You can choose from the following:
  • Oyster
  • Shiitake
  • Reishi
  • Enoki
  • Turkey Tail
  • Lions Mane
  • Medicinal Tinctures
  • Consultation Services