Written by John Holliday on Oct. 17th 2015
Biological Efficiency, or BE, is THE MOST IMPORTANT THING you need to understand to assess how your mushroom farm is doing, for without following this simple metric, you have no way to know how your production process is going. Once you understand the concept of BE, you can and will use it to track everything on your farm. BE is the ratio of the dry weight of substrate to the harvest of fresh mushrooms. We all buy our substrate dry in the back of a truck. Let’s say you buy a load of sawdust – 1000 pounds – you need to know how many mushrooms you will get from that sawdust. If you are able to harvest 1000 pounds of fresh mushrooms, that would be a BE of 100%. Well, that’s not exactly right, because the sawdust you bought had some moisture in it already. It may be 10%, maybe more. Let’s assume the sawdust has a moisture content of 10% coming in. This feels dry to the touch, but 10% means that 100 lbs out of the total weight of sawdust – 1000 pounds – is water. So what you really have is 100 pounds of water, and 900 pounds of dry sawdust nutrient. That means you will really get 900 pounds of fresh mushrooms if you are achieving a BE of 100%
ANY species of mushroom that can be commercially cultivated, and there are more than 180 species in cultivation today, will achieve OVER 100% BE when everything is done correctly. In fact with all my farms, I use 100% BE as the baseline. We simply MUST get 100% BE to be profitable, it is as simple as that. Many mushroom species typically will get far over 100% BE. For example, Oysters will typically get around 170% BE, and Calocybe Indica (White Tuscany Mushroom) often achieve from 250% to 300% BE!
I am often asked, how can anything get higher than 100% BE? Isn’t that against the law of nature, getting more out than you put in? Not exactly – what we are putting in is water. The DRY weight of the nutrient in the substrate is what determines the BE, but up to 94% of the fresh mushroom weight is water. So it is not difficult to get above 100% BE. It is water weight. And us mushroom farmers, well, we just LOVE to sell water!
So why is this so important to know and to track? Virtually EVERYTHING on your farm or in your process has an influence on BE. Let’s say you change spawn suppliers as an example. How do you know the new spawn supplier is sending you spawn as good as the spawn you used before? You can ONLY tell that be tracking the BE! Or let’s say you are making your own spawn, a very common mistake made by nearly all new mushroom growers. How do you know your spawn is really good? Because you followed a recipe from a book? WRONG! Because you learned from someone whom you think taught you well? WRONG! The only way you know if your spawn is worth using is to test grow a few batches with it and measure the BE. If you are at or above 100% BE, great! But you will be surprised when you actually measure the BE. More than 95% of the clients I have worked with over the last 40 years, and there are literally thousands of them, actually found they were getting less than a 50% BE when they got around to measuring it! It does not cost you any more to get 100% BE, or 150% BE than it costs to get 25% or 50%. The costs are the same going in – the same substrate, spawn, energy, labor, the same dollar value per bag. It is only the yield that changes. Why settle for 30% or 40% BE when you can make a few changes and get 100%, or 150%?
Another example – when you get your next load of substrate, how do you know it is going to perform as well as the last batch? Or that it is nutritionally balanced for the species of mushroom you are growing? Does it need any amendments? Are you wasting money by using too many amendments? All these questions can ONLY be answered by looking at your BE.
If you would like some help in getting your BE up to where it should be, contact us for a free strategy session and we will talk it over to see if we can help you out.
Dr. John Holliday
Dr. John helps people start and grow successful mushroom cultivation businesses. He is an expert at growing all species of exotic mushrooms by integrating modern biotech methods and making things super simple to understand.
If you’re interested in starting your own mushroom business or scaling up and increasing your profits then definitely reach out and request a free strategy session today.
