As sustainable practices gain popularity, the integration of human manure into mushroom cultivation has caught the attention of eco-conscious growers. While the idea might seem unconventional, human manure holds potential in both substrate preparation and composting systems. This article explores how human waste can be used for cultivating mushrooms like Agaricus, Psilocybe cubensis, and Coprinus comatus (Shaggy Mane), and how mushroom spent blocks can help reduce odors in compost toilets.
Can Mushrooms Grow on Human Manure?
Mushrooms naturally thrive on organic matter, and some species can grow on manure. While human manure has been less commonly explored in traditional mushroom cultivation compared to animal manure, it offers similar nutrient profiles that certain fungi can utilize. However, for safety reasons, it’s essential to ensure that human waste is fully composted before use as a substrate to kill harmful pathogens.
Mushroom Species That May Thrive on Human Manure:
Agaricus bisporus (Button Mushrooms): These mushrooms are typically grown on composted manure. Although horse and cow manure are the most common substrates, humanure—once properly composted—could provide a viable alternative for sustainable cultivation.
Psilocybe cubensis (Psychedelic Mushrooms): Known to grow on manure in the wild, Psilocybe cubensis is a popular species for mycologists. There’s potential for humanure to serve as a substrate if thoroughly processed to ensure safety.
Coprinus comatus (Shaggy Mane): Shaggy mane mushrooms are often found growing in nutrient-rich, decaying organic matter, including manures. This adaptability suggests that composted human manure could support their growth.
Using Human Manure as a Substrate for Mushrooms
When properly composted, human manure becomes a nutrient-dense medium that can serve as a substrate for certain mushrooms. Here’s how you can safely use humanure in mushroom cultivation:
Steps for Composting Human Manure for Mushroom Substrate:
1. Hot Composting: Maintain temperatures between 130°F and 160°F during the composting process to eliminate pathogens, making the manure safe for mushroom cultivation.
2. Mix with Organic Material: Combine the composted manure with straw, wood chips, or other carbon-rich materials to create a balanced substrate. This mixture mimics the nutrient profiles that species like Agaricus bisporus and Psilocybe cubensis thrive on.
3. Inoculate with Mushroom Spawn: Once the substrate has cooled and stabilized, inoculate it with your mushroom spawn and monitor the colonization process.
By using humanure as a substrate, you’re contributing to a circular economy, reducing waste, and promoting sustainable agriculture.
Spent Mushroom Blocks for Compost Toilets
Spent mushroom blocks—used substrates from mushroom cultivation—can be a game-changer for compost toilets. These blocks, rich in mycelium and decomposing organic material, not only break down waste faster but also help mitigate odors, creating a more pleasant experience for users.
How to Use Mushroom Spent Blocks in Compost Toilets:
1. Layering with Human Waste: After each use of the compost toilet, layer a small amount of spent mushroom blocks over the human waste. This helps absorb moisture and introduces beneficial microorganisms that speed up the decomposition process.
2. Neutralizing Odors: The mycelium in spent mushroom blocks helps neutralize the odors often associated with composting toilets by breaking down the organic matter more efficiently. This can make a compost toilet nearly odor-free, especially when combined with sawdust or coconut coir.
3. Accelerating Composting: Spent mushroom blocks contain residual nutrients and mycelial activity, which can help break down human manure more quickly, resulting in rich, nutrient-dense compost.
Advantages of Using Spent Mushroom Blocks in Composting Toilets:
Odor Control: The mycelium in spent blocks works as a natural deodorizer.
Faster Decomposition: Mushroom blocks enhance microbial activity, breaking down waste faster and more effectively.
Recycling Waste: By reusing spent mushroom substrates, you’re not only improving your compost toilet but also making the most of your cultivation waste.
Sustainability and Safety: Composting Humanure for Mushrooms
When using human manure for mushroom cultivation or as a compost toilet additive, safety and sustainability are key. Proper composting ensures that harmful bacteria and pathogens are eliminated, making the end product safe for use in mushroom substrates or as fertilizer.
Best Practices for Safe Humanure Use:
1. Extended Composting Time: To ensure humanure is fully decomposed and pathogen-free, allow it to compost for at least a year before using it for mushrooms.
2. Monitor Compost Temperatures: Consistently high temperatures are necessary for killing off harmful organisms. Turning the compost pile regularly helps maintain these temperatures.
3. Separate for Non-Edible Crops: If you’re unsure about using human manure in direct mushroom cultivation, consider using the composted material for non-edible plants or myco-remediation projects instead.
Conclusion
Human manure has significant potential in sustainable mushroom cultivation when properly composted and utilized. From serving as a substrate for species like Agaricus bisporus and Psilocybe cubensis to being a natural deodorizer in compost toilets with spent mushroom blocks, humanure offers an eco-friendly solution for reducing waste. By experimenting with these techniques, growers can create closed-loop systems that benefit both the environment and their crops.
