Using Mountain Microorganism to Create Organic Fertilizer

Using Mountain Microorganism to Create Organic Fertilizer

By 2019 RM Apprentice Amy Dodds

The need to cultivate a “living soil” that is full of microbes is something I hear frequently in the organic farming and permaculture world. As an apprentice at Rancho Mastatal this year, I have the unique opportunity to look further into the universe of these small and unseen allies. A way into this world was through the Ranch’s process of making organic fertilizer, one that harvests and inoculates the soil with Mountain Microorganisms (MM). This is similar to compost tea, where we create a fermented fertilizer with microorganisms such as manure. MM differs from this by using forest soil and duff layer to create a fertilizer. You can create MM fertilizer anywhere in the world so long as there are forests in your area that has a healthy amount micro life!

In just the second week of our apprenticeship, the Ranch hosted guests from Ecogrecia, another local farm and research centre who are using MM. We were were privileged to get a demonstration of how we can cultivate our own indigenous microorganisms. I will detail this below so you can create your own MM fertilizer but first here’s a bit on the science.

There are many diverse living organisms that improve the soil ecosystem, these include invisible bacteria and fungi and visible worms and insects. A few of the benefits of fostering this micro-community include: aeration of the soil, making nutrients available, fix nitrogen and prevent pathogens. With this in mind we want to cultivate soil in our orchards that is full of microbial life.

Agro-forestry systems at Rancho Mastatal

Agro-forestry systems at Rancho Mastatal

Our main farming practice at the ranch is agro-forestry. This is essentially using trees with other crops to create an ecosystem that mimics the tropical rain forest environment of Costa Rica. Most forests need a fungal dominated ecology, while still needing bacterial organisms, for optimal soil. The “fungal to bacterial biomass ratio” needs to be 10 parts fungi to 1 part bacteria. Especially important is the mycorrhizal fungi that live closely with tree roots to allow the plant to take up nutrients and water. Therefore we want to harvest a fungal dominated fertilizer. In the past Rancho Mastatal has used manure fertilizers which work well for gardens and vegetables but are less tailored for forest soils, due to their high bacterial rate. This is where Mountain Microorganisms come in!

Mountain microorganisms was originally a Japanese practice that take forest leafs and soil from native forest within the land you are growing in to create an anaerobic ferment (without oxygen). I see this is as beautifully symbiotic as we are inoculating the soil with indigenous microbes from the local environment. We essentially take the mother culture which contains the diversity and variability perfectly suited for your local forest.

Mountain microorganism fertilizer is a better process for our agro-forestry systems, than say compost tea made from manure, due to the high fungal microbes available in our mother culture. Rancho Mastatal has been using the MM process consistently for 3-4 years and noticed improved conditions in their food forest.

One of the first steps in this process, which we did with our apprentice team and the crew from Ecogrecia, is going into the forest and gathering the local microorganisms to create our current solid fermentation. Around the large well established trees, we harvested leaves and sticks that are crumbly and breaking down. They have the delicious white mycorrhizal growth on them. Under the leaves we collect the soil that contains the visible fungi.

Spraying the orchards with an organic fertilizer

Spraying the orchards with an organic fertilizer

From this we can create a solid fermented product and then a foliar spray that will inoculate our soil with the microbiology that we need to improve our soil life. Once it is in foliar spray form we take our backpack sprayer once a week to our orchard trees. Below are the recipes for creating your own microorganisms:

Mountain Microorganism Recipe

MM Solid

3 sacks of Microorganisms
-        This is the duff layer of brown leaves and sticks that contain the mycorrhiza

2 sacks of semolina
-        This acts as the protein, other flour work such as yucca or green banana

1 gallon of molasses
-        This is the sugar that provides the microorganisms with energy
-        Alternatives include fruit or cane juice

1 gallon of water to dilute molasses
3kg of rock dust phosphate
55 gallon plastic drum to store (never metal) 

Mix a layer of the duff with the semolina on a tarpaulin with your hands. Sprinkle the molasses and water over this as you are mixing layers of the duff and semolina.

Shovel the mix into your drum, while you have a friend stamp inside to compress and release any air (as this is an anaerobic ferment). Seal well and store for at least one month in the shade.

This lasts 3-4 years :)

mixing the the recipe above

mixing the the recipe above

MM Foliar Spray

5 kg MM Solid
1 gallon of molasses
55 gallon plastic drum filled with water

Add the molasses to the water. Use a screen sack to hang the MM into the liquid. Seal and let it sit for 5 days.

 Use within 3 weeks.

 When applying as a foliar spray, you can dilute with water. Make sure there is at least 10% MM liquid to be effective.

Inoculating the soil with micro-life is only one step in this process. Fungi thrive in high carbon environments so mulch, mulch, mulch! Watering and composting still need to be continued, especially in the tropical dry season.

Happy foresting and fermenting!

 If you are interested in Permaculture and Agroforestry check out some of our upcoming workshops!


Jeff Lowenfels & Wayne Lewis Teaming with Microbes: A Organic Gardener’s Guide to the Soil Food Web (2010)

Craig R. Elevitch & Kim M. Wilkinson The Overstory Book: Cultivating Connections with Trees (2001)

Phil Nauta Building Soils Naturally: Innovative Methods for Organic Gardeners (2012)

Scott Gallant Making Microbes: Fungal vs Bacterial Soil Life