Bat Guano and Cannabis Farming

If you’re an avid gardener, you may have heard about the benefits of using bat guano as an organic fertilizer. Derived from the excrement of bats, bat guano is a highly effective and nutrient-rich substance, ideal for the growth and development of cannabis. 

In this article, we’ll explain what exactly bat guano is and how bat guano can be used to enhance the quality of your garden when growing cannabis.

What is bat guano?

The word “guano” comes from Quechuan, the language of the indigenous people of Peru. Based on archaeological evidence, the Quechuan people are believed to have collected the excrement of seabirds such as guanay cormorants and pelicans from the coastal islands. Due to their fish-based diet, their excrement is rich in nutrients, making it a popular choice for farmers seeking a fertility-enhancing and natural fertilizer.

Bat guano, produced by cave-dwelling bats, was highly sought after during the Age of Exploration due to its nutrient-rich composition. This fecal matter contains high nitrogen content, phosphorus, and potassium, promoting growth, increasing yields, and enhancing microbial activity. Although its popularity declined with the rise of synthetic alternatives in the mid-20th century, bat guano is still widely used today due to its numerous benefits.

Guano is also essential in the production of gunpowder and is also used in some medicines. However, there is some controversy surrounding its use. The Chincha Islands War, which took place in the mid-19th century, was fought over guano-rich islands by Spain and a coalition of Peru, Bolivia, and Chile. Later, it was discovered that inhaling its dried spores can cause a severe respiratory disease called histoplasmosis. 

Exploring the nutritional value of bat guano: micro and macro nutrients

Bats are carnivorous animals, and their diet can impact the nutrient content of their feces. Microbats prefer to consume insects, including moths, beetles, mosquitos, and crickets. This gives their feces high phosphorus levels, supporting plant growth during the vegetative cycle. At the same time, megabats are more likely to feed on fruits, pollen, and nectar. Their feces contain high potassium levels, promoting the development of denser and resinous flowers.

But what other beneficial compounds can be found in bat guano?

• Boron               

Boron is essential for the growth and development of plant roots and cell membranes.

• Calcium

Calcium enhances plant growth and development by improving nutrient absorption and translocation. 

• Iron                  

Iron helps form chlorophyll, which is essential for absorbing light to produce food and energy. It also contributes to pigmentation. 

• Manganese

Manganese is crucial in nitrogen metabolism. It impacts chlorophyll and protein synthesis while supporting robust root growth and structural development.

• Magnesium      

Magnesium helps produce amino acids, which promote robust growth, bud development, and germination. 

• Sulfur

Sulfur contains amino acids, which help robust growth and structural development.

• Zinc

Zinc produces enzymes for making carbohydrates, proteins, and chlorophyll, which are essential for healthy plant growth and development.

When to use bat guano for weed

Bat guano can be used as a naturally sourced fertilizer to benefit the growth of cannabis plants during both the vegetative and flowering stages. However, it is important to be cautious when using it, as applying it excessively or too soon can lead to nutrient burn. 

To avoid this, it is recommended that you refer to our guide on common cannabis deficiencies to identify any symptoms. So, let’s review some important points to consider before applying bat guano to cannabis cultivation.

Vegetative Stage:

The vegetative stage of cannabis plants focuses on developing a strong root zone and robust structure. Bat guano can be applied as a soil amendment before planting or during the early stages of vegetation to provide a slow-release source of nutrients that support healthy root development and vigorous vegetative growth.

Flowering Stage:

Bat guano can be used during the flowering phase to encourage robust bud development and improve terpene and cannabinoid production. However, if you notice yellow leaves starting at the bottom of your plant and moving upwards, this may be a sign that you are using too much fertilizer, which can lead to nutrient deficiency. 

How to use bat guano

There are two main ways to use bat guano for cannabis cultivation.

• Soil amendment:
  If you plan to use bat guano as a soil amendment before planting, mix it thoroughly into your medium rather than just spreading it over the soil’s surface. Doing so will provide a slow-release source of nitrogen, phosphorus, and potassium. This will promote healthy root development and vigorous growth throughout vegetation and flowering.

• Liquid fertilizer:
  Using liquid nutrients is a highly effective method to enhance the overall health of your soil and plants throughout the different phases of the growing cycle. Bat guano, when dissolved in water, can be directly applied to the roots of your cannabis plants. Below, you will find our recipe for bat guano tea.

Cannabis Bat Guano Tea Recipe

If you want to improve your garden’s fertility with bat guano, you can mix it into liquid fertilizer, such as compost tea, to provide your plants with an excellent source of nutrients. To make your very own guano tea, you’ll need the following supplies:

• Distilled water
• Sieve 
• Storage container

Follow this step-by-step guide for making your bat guano tea. 

1. To prepare this tea, you’ll need one tablespoon of guano per liter of distilled water. For example, mix one cup of guano with ten cups of warm water in a ratio of 1:10.

2. First, fill your container with distilled water and warm it to room temperature. Then, add the guano and stir the water until the guano is fully dissolved.

3. Cover the container with a lid and let it sit for 24 hours. This will allow the nutrients to infuse into the water, creating a nutrient-rich tea that’s perfect for your plants.

4. After letting the mixture steep overnight, it will reach the desired strength, and the tea will be ready for use. Strain it through a fine mesh sieve to remove any leftover guano bits, and then pour it around the base of your cannabis plants.

Adding aeration (aka additional airflow) will make a much better tea. Without aeration, microbes can potentially suffocate, which creates a tea that is harmful to plants.

What not to do with bat guano

Firstly, when using any fertilizer, using bat guano in moderation is recommended to prevent over-fertilization, which can cause nutrient imbalances. Always be vigilant and regularly check the pH levels of your medium to ensure an aesthetically pleasing growing environment. Now, let’s share some expert tips that can help you make the most of organic fertilizers!

• Don’t breathe it in, as it contains toxic elements and can harm your health. Wear a face mask during application.
• It is recommended to use bat guano in moderation to prevent over-fertilization, which can cause nutrient imbalances.
• To prevent degradation, storing it in a cool, dry place out of sunlight is crucial.
• Use teas and liquid fertilizer within 24 hours of mixing to avoid the buildup of unwanted bacteria and pests. 

 FAQs

Is bat guano good for weed plants?

Feeding your plants bat guano can be beneficial as it contains nutrients cannabis plants require. However, it must be applied in moderation at the right intervals to avoid nutrient burn.

What does guano do for cannabis?

Guano is good for cannabis thanks to its rich nutrients essential for boosting microbial life. It can be applied to soil mix or used in liquid fertilizer tea in a 1 to 10 ratio.

Can you use too much guano?

Yes, it’s important to use guano in moderation to avoid nutrient burn. 

What’s the best way to feed bat guano to cannabis plants?

Guano can be applied to plants in soil amendments or liquid fertilizer. Some growers opt to create teas or mix with water for feeding.