Some growers are put off by the idea of using organic methods, like making your own compost tea or worm composting, because it is considered more difficult and time consuming. There is, however, a product that is widely available and is a balanced, natural organic fertilizer used for fruiting and flowering plants. That product is guano, most commonly sourced from bat feces. In farming and gardening, guano has many uses.

The Gift of Guano

The word “guano” originated from the Andes area of South America and refers to any feces (usually sea birds and bats) used for crop fertilization. Andean people are believed to have used it for this purpose beginning more than 1,500 years ago, collecting it from small islands off the desert coast of Peru. Guano is found in extremely dry climates where rainwater cannot leach the nitrogen rich ammonia out of the guano. Islands and coastlines where there is intense marine upwelling, such as along the eastern side of the Pacific and South Atlantic oceans, are the perfect location because large colonies of marine birds congregate for easy to their respective food sources that include, fish, insects and fruit. Bat guano is sourced from rainforest caves in locations like Madagascar and Indonesia, where insects and fruit are plentiful, and the guano is unaffected by climatic changes, preventing any leaching of nutrients.

However, it is important to ensure the guano used is ethically sourced and harvested under strict preservation guidelines to avoid disrupting the respective creatures’ habitat.

Guano's beneficial properties have been recognized from as early as the 16th century when the Inca Empire restricted access to guano sources and punished anyone who disturbed them with death. Three centuries later, Western culture began to import guano on a large scale. After that, guano became a valuable commodity in regions where it was mined, helping with economic development, while being the catalyst for disputes over land ownership as people clamored to own the valuable rights to harvesting it.

Multi-functional Fertilizer

In today’s agricultural market, bat guano is the most commonly available product and is sought by indoor and outdoor growers. So, what does it do and how do you use it?

Bat guano is high in essential nitrogen, phosphorous, and potassium with the nitrogen-phosphorus-potassium (NKP) ratio typically being 10-3-1. These are the three primary nutrients plants need, and they assist in many major plant functions such as quick green growth, strong root development, flowering, and healthy stems. It is important to note, however, that due to its organic nature, the nutrient levels cannot be guaranteed. Because of this, growers often use it as a supplement alongside appropriate fertilizer products as required by your crop species.

A multi-functional fertilizer, guano can also be used as a soil conditioner, enriching the soil with NPK and trace minerals, while improving drainage and texture. Guano is also a lawn treatment due to its abilities to encourage rich green growth, a fungicide when applied to leaves, and a compost activator which speeds up the decomposition process of compost matter and can also control harmful nematodes in the soil.

The microbes in guano fertilizer have been reported to aid with cleansing toxicities from the soil, improving the natural balance without increasing alkaline or acid levels, while providing the soil’s biological system with fast and slow release nutrients. As with all-natural manures, the time taken to break down the nutrients into a plant-soluble form will be longer than when using non-organic fertilizer.

The benefits of using guano can be experienced in end products too, with many experienced growers of edible crops claiming guano positively enhances the taste of their produce by making the overall flavor sweeter, richer, and less watery.

Easy to Use

Other benefits of using guano include its low to non-existent odor, its fast action (in comparison to other natural manures), and its resistance to burning plants and roots, made possible by its slow release of minerals.

Guano can be worked into soil prior to planting or applied as plants are growing. It is versatile in application and can be used fresh or dry, though it is most commonly sold commercially in powder, pellet, or liquid form. Dry guano can be mixed with water to form a manure tea by using roughly a cup measure of guano per gallon of water. Let it stew overnight, then strain and use. Due to its potency, you will notice the application rates for guano are smaller than those of other types of manure. Pay close attention to the directions on the packet as dosages will differ depending on the lifecycle stage your plant is in, what the plant species is, and the form of guano being used.

Leave Harvesting to the Professionals

As well as bat guano works in your garden, it goes without saying individuals should not attempt to harvest bat guano on their own. Bats feces, when untreated, is especially dangerous and can carry histoplasmosis capsulatum, which is a fungus which can make people very sick with the histoplasmosis virus. People get the virus when inhaling the fungal spores. It usually affects the lungs and occasionally the eyes and varies from mild flu-like symptoms to causing chronic lung disease. There are many safety precautions and processes guano undergoes when it is commercially produced to ensure it is safe when bought and used by consumers.

When it comes to guano, it seems too good to be true, but it’s hard to argue with thousands of years of use and success. It is also a sustainable, organic, and completely natural product.