The Best Substrates for Growing Mushrooms at Home: A Deep Dive into Animal Dung-Based Options

Mushroom cultivation at home has gained massive popularity in recent years, and one of the most important factors in a successful grow is choosing the right substrate. The substrate acts as the food source for mycelium, providing the necessary nutrients for mushrooms to thrive. Many different materials can be used as a substrate, but for certain mushroom species, animal dung is an especially beneficial addition.

Common Mushroom Substrates

Mushroom substrates vary depending on the species being cultivated. Some of the most common substrates include:

Hardwood sawdust or chips – Ideal for species like Lion’s Mane and Shiitake.
Coco coir and vermiculite – A popular mix for growing many gourmet and medicinal mushrooms.
Straw – A great choice for Oyster mushrooms.
Manure-based substrates – Essential for dung-loving mushrooms like Psilocybe cubensis.
Coffee grounds – A sustainable option that works well for species like Oysters.
Composted materials – A mix of organic matter that provides a rich nutrient base.

Among these, manure-based substrates are particularly important for cultivating certain fungi that thrive in nutrient-rich environments.

Why Use Animal Dung in Mushroom Substrates?

Animal dung is packed with organic material and beneficial microorganisms that help fungi break down complex nutrients, making them highly bioavailable. Many mushrooms, especially Psilocybe cubensis and other dung-loving species, naturally grow in manure-rich environments. Adding dung to a substrate can boost yields, improve colonization speed, and enhance the overall robustness of the mushrooms.

Ranking Animal Dung for Mushroom Cultivation

Not all animal dung is created equal when it comes to mushroom cultivation. Here’s a ranking of different types of dung, from best to worst:

1. Alpaca Manure (Best Choice)

Why? Alpaca manure is an exceptional substrate choice because it has a near-perfect balance of nutrients, excellent aeration, and low ammonia levels. It naturally supports robust mycelial growth while maintaining proper moisture retention without becoming too dense.
Best for: Psilocybe cubensis, Agaricus species.
Preparation: Requires minimal aging, but should still be dried and leached to optimize conditions.

2. Horse Manure

Why? Horse manure is considered one of the best dung options for mushroom substrates. It has a high fiber content, excellent water retention, and a balanced nutrient profile that supports healthy mycelium growth.
Best for: Psilocybe cubensis, Agaricus species.
Preparation: Aged and leached to remove excess ammonia and nutrients.

3. Cow Manure

Why? Cow manure is another excellent choice, though it can sometimes be too wet and dense, requiring additional bulking agents like straw or vermiculite.
Best for: Psilocybe cubensis, Agaricus species.
Preparation: Should be well-aged and mixed with straw or other aerating materials.

4. Donkey and Mule Manure

Why? Similar in composition to horse manure, it provides good water retention and a balanced nutrient profile.
Best for: Psilocybe cubensis and similar dung-loving species.
Preparation: Dried and aged properly to prevent excess ammonia.

5. Rabbit Manure

Why? Rabbit manure is rich in nitrogen and doesn’t require aging, but it’s best when mixed with other bulk substrates to balance the nutrient density.
Best for: Oyster mushrooms, Psilocybe cubensis when mixed with straw or coir.
Preparation: Can be used fresh but is often composted for better consistency.

6. Goat and Sheep Manure

Why? These manures tend to be lower in fiber and may require additional supplementation to improve aeration and structure.
Best for: Limited use in mushroom cultivation; may be mixed with other materials.
Preparation: Should be aged and mixed with a more fibrous substrate.

7. Chicken Manure (Worst Choice)

Why? Chicken manure is too high in nitrogen and ammonia, making it too hot for most mushrooms. It can kill mycelium if used in large amounts.
Best for: Not recommended unless heavily composted and diluted with other materials.
Preparation: If used at all, it must be aged and composted thoroughly.

How to Prepare a Manure-Based Mushroom Substrate

Using manure as a substrate requires proper preparation to remove harmful ammonia and ensure a balanced nutrient content. Follow these steps:

Aging and Leaching – Fresh manure contains high levels of ammonia, which can be toxic to fungi. Let it age for several weeks and leach it by exposing it to rain or soaking and draining.
Pasteurization – To kill off unwanted bacteria and contaminants, pasteurize the manure by heating it to around 160°F (70°C) for 60–90 minutes.
Mixing with Other Materials – For the best results, combine manure with bulk materials like straw, coir, or vermiculite to improve aeration and moisture retention.
Hydration Check – Ensure the substrate holds moisture well but is not overly saturated. A good rule of thumb is the “field capacity” test: squeeze the substrate, and it should hold shape without dripping excessive water.

Final Thoughts

Animal dung-based substrates are some of the best options for growing dung-loving mushrooms, especially Psilocybe cubensis and Agaricus species. While alpaca and horse manure rank at the top, chicken manure should be avoided due to its high nitrogen content. With proper preparation, manure-based substrates can significantly improve mushroom yields and overall growth. Whether you’re a beginner or an experienced grower, understanding how different substrates impact mushroom cultivation is key to successful harvests. If you’re working with dung-based substrates, be sure to age, pasteurize, and mix them correctly to create an ideal growing environment.