Yes, mushrooms do need sugar to grow. Sugar is a source of carbon, which is an essential nutrient for mushrooms. In the wild, the mushrooms obtain carbon from decomposing plant matter. Their mycelium can break down complex matter like hardwood logs and convert it into starch and simple carbon compounds it needs for growth. In substrates, sugar or other starch forms like rye grain and straw provide most of the needs that mycelium needs to grow.
The challenge is determining which type of sugar is good for mushroom growth. The general wisdom is that the sugar contained in the grains used for substrates is enough, especially if you used grain as substrates. However, several studies show that having a certain sugar concentration percentage is beneficial in the growth of spawn mycelium, accelerating its growth. In the study, dextrose proved to be the best source of carbon for mushrooms. At a dextrose concentration of 2% of the PDA medium, the pinhead development took the least amount of days.
Caution should, however, be observed when adding sugar to the substrate. The more suitable an environment you create, the more likely you are to attract contamination from mushroom competitors like molds, bacteria, and other fungi. It is for this reason that the substrates are usually pasteurized or sterilized. More complex carbon sources are also preferred since, while mushrooms take slower to grow, they have an advantage when it comes to breaking down complex carbs into food.
Other Nutrition Needed by Mushrooms
Carbon is not the only nutrition needed by mushrooms. They also need lignin, fats, and nitrogen. Carbon and nitrogen are recognized as the main macronutrients for mushrooms. These two are responsible for the structural and energy requirements of the mushrooms. Phosphorus, Potassium, and Magnesium are also essential for the growth and development of mushrooms. Trace amounts of iron, zinc, manganese, selenium, and copper are micronutrients that are used for diverse functions by the mushrooms. Mushrooms also need oxygen and specific pH levels to grow.
Supplements are added to the compost or substrate during spawning or casing phases to boost the supply of these nutrients. These nutritional amendments increase yields and, in some cases, lead to higher nutrition makeup in the harvested mushrooms.
Several commercial products contain a blend of protein, lipids, carboxylic acids, and minerals. You can also have low-cost agricultural by-products, which include;
· Chicken manure
· Cereal meals and bran
· Grapeseed meal
· Olive mill waste
· Soybean nuggets and soy cake powder
· Corn and oat husk
· Palm fiber
· Carrot pulp
· Sugar beet pulp
The right timing and method of application are crucial to obtain the expected results. Studies show that using supplements that delay the release of nutrients, such as treating them with formaldehyde, is beneficial. It limits the availability of the nutrients to competing molds. When the mushroom mycelium becomes dominant, it can take advantage of the gradually available nutrition.
Why Do Mushrooms Require External Nutrition?
Mushrooms are fungi, which makes them heterotrophic organisms. They, therefore, need external nutrients to grow. They have no chlorophyll like plants to make their food. For nutrition, they break down the non-living organic matter around them using enzymes and acids they release. They also have to digest the food externally before passing through to the cell wall to the hyphae that absorb the nutrients. By providing extra nutrition in the substrate, you, therefore, accelerate the growth of mushrooms.
Care should be taken when adding nutrition, especially sugar, to avoid contamination. Also, too much of it may stall or slow down the growth of the mushrooms.
Other Factors Mushrooms Need to Grow
Mushrooms need a growing medium, which could be logs, dung, mulch, compost leaves, etc. Commercially grown mushrooms require a specially prepared medium, usually a combination of manure and straw.
Water and Humidity
Mushrooms need moisture for fruition. Since they lack a skin membrane, the water is easily lost, and thus they need an environment with high humidity to prevent water loss. If the water is too much, however, it can drown them. The soil should be moist, not wet.
Mushrooms do not carry out photosynthesis; thus, they need no light to grow. They only need dim light to help form the fruit bodies. Filtered light like indirect sunlight or a fluorescent lamp is enough.
Mushrooms prefer a cool environment and generally do well in temperatures around 55 to 60 degrees Fahrenheit. The fruits appear when temperatures reach 50 to 70 degrees Fahrenheit.