Mushroom Compost: Where to Buy and How to Use 

There are a lot of materials you can use in composting. They can include green vegetables and old newspaper. You can also source for high-quality compost for your garden by purchasing mushroom compost. 

Mushroom composts are waste products derived from the industrial production of mushrooms. These mushroom composts mainly consist of organic matter such as horse dung, wheat straw, ground chalk, and dried blood. Mushroom compost can provide your plants with adequate nutrients to support healthy growth. 

When composted properly, mushrooms can provide your soil with 0.7% Nitrogen, 0.3% Potassium, 0.3% phosphorus, and other trace elements. Mushroom compost acts as a quality soil conditioner and can be used to add nutrients to mineral-deficient soils. 

When shopping for mushroom compost to use in your garden, you want to ensure that you check that the pesticide content is low. When mushroom compost is produced in the industry, chemicals are often added to treat the straw and to ward off gnat and other insects from the decaying matter. For the best mushroom compost, you want to ensure that there are no chemical compounds added to the mix to avoid contamination of your plants. 

Before you can truly understand how to use mushroom compost, you need to first familiarize yourself with what mushroom compost is. 

What is Mushroom Compost?

Mushroom compost can simply be identified as a compost material that is made from mushrooms. They are available for purchase from organic soil markets where they are often referred to as mushroom soil. It contains rich amounts of nutrients like Phosphorus, Nitrogen, and Potassium. Three key minerals that your soil needs to support healthy plant growth and development. 

Before you go shopping for mushroom compost, you need to know that there are various types of mushroom compost available in the market. While all of them are made from mushrooms, they each undergo a slightly different kind of manufacturing process that affects the quality of the resulting compost. 

The different types of mushroom compost include: 

  • Mushroom Substrate

The mushroom substrate is the common type of mushroom compost you can find. The process of manufacturing mushroom substrate usually involves making use of a medium that includes a mix of ingredients. The ingredients used in the substrate can be a mix of chicken or horse manure and gypsum or wheat straw. Other ingredients can be used as a substrate, but these are the most commonly used. 

The production process usually begins with the addition of large bales of wheat straw to cool water and leaving it to soak for 5 to 10 minutes. Once the straws are completely moist, it is then cut into tiny pieces by the help of a chipper. The manufacturer then blends the gypsum and manure together, and then slowly includes the chipped straw into the mix. The resulting mixture is now kept in hot compost piles and left for 2 to 3 weeks. For the best result, the piles will have to be turned and watered regularly to speed up the decomposition process. After the wheat seeds have died off from the excess heat, the piles are then transferred into rows and left out for a few more weeks to further compost. 

The compost pile will be ready for pasteurizing once the piles appear brownish in color. The reason for pasteurizing is to kill any weed seed or bacteria that are left in the compost. The resulting compost is clean and ready for use in growing mushrooms. 

  • Spent Mushroom Substrate

Spent mushroom substrates are the type of mushroom compost you purchase from mushroom farms. They are termed “spent” because they are no longer fit for use in growing mushrooms but can be recycled by adding it to a compost pile. 

Compared to the mushroom substrate, these types of mushroom compost are low in nutrients and can only be used in amending soil nutrients. They are often used as lawn conditioners to improve the quality of the soil. The straw content in spent mushroom substrates is a good organic material that helps improve the water retention of the soil. This makes it a good addition to a raised bed medium or planting mix. 

Mushroom Compost How to Use and Where to Buy

You are likely to find mushrooms growing in your garden when you make use of spent mushroom substrates. I strongly advise not to eat the mushrooms you find in your garden (as a result of spent mushroom substrate) so as to avoid consuming any chemical compound that might have been added to the mix. Carefully remove any mushroom as soon as they appear to prevent them from reaching maturity. 

  • Substitute Mushroom Compost

Other materials can be used in mushroom compost. But before they are added, they are pasteurized to kill off all the bacteria that can encourage the growth of mold. Some of the popular materials used in substitute mushroom composting include coffee grounds. This is because it is readily available and can be purchased for use in a home-base mushroom growing setup. You can purchase coffee grounds for free from commercial coffee shops depending on your area. 

Mushroom Compost How to Use and Where to Buy

Other materials that are used as a mushroom compost base include horse or chicken manure, coconut coir, peat moss, soybean meal, and hardwood dust. Once these materials are broken down, they can provide your soil with organic matter that can improve nutrient availability for healthy plant growth. 

Uses of Mushroom Compost

You can use mushroom compost on your plant soil as:

  • A slow-release fertilizer to neutralize acidic soil. 
  • Added to clay soil to improve water retention. 
  • Fresh manure compost can be used as mulch for your plant root. 
  • A dresser for the top of your lawns to prevent the growth of weed. 
  • Mushroom compost can be used in vermicomposting as a worm bed
  • It can be added to a tumbler composter to speed up the decomposition process. 

Where to Buy Mushroom Compost

You can purchase mushroom compost from mushroom manufacturing industries and farms or in big box stores like Home Depot or Lowes.

They are also available for purchase online for use in soil amendment. You can also make your own mushroom compost at home following simple methods we have outlined above. 

Do you use mushroom compost in your garden? What materials do you use in composting?