(888) 349-0605 M-F: 10-7 EST

Guano: What Is It + How to Use It in Your Home Gardens

Bat guano in spoon used as a fertilizer

Guano, often known as bird or bat droppings, is a potent organic fertilizer that has been used in agriculture for centuries. It is rich in nutrients, including nitrogen, phosphate, and potassium, which are essential for plant growth. Its high nutrient content and organic nature make it an excellent choice for organic farming.

Bat guano, in particular, is highly sought after as it is believed to be superior to other types of guano. The bats’ diet of insects and small creatures results in guano that is exceptionally rich in nutrients. Moreover, it is a sustainable resource, as bats produce it continuously.

However, while guano is beneficial for plants, it can pose a risk to humans and pets if not handled properly. It can harbor disease-causing fungi and bacteria.

Therefore, it’s crucial to use proper protective equipment when handling guano and to ensure it is properly processed before use.

In this article, I’ll go through everything you need to know about guano, including the safety precautions and how to use it in your home garden.

What is Guano?

Guano is a term that may not be familiar to many, but it’s a common substance in the world of pest control. Simply put, guano is the excrement of birds and bats.

While this may not sound particularly appealing, it plays a significant role in the ecosystem and has various applications in agriculture and gardening due to its high nutrient content.

The word “guano” originates from the Quechua language, used by the indigenous people of the Andes, and it means “the droppings of sea birds.” Over time, the term has expanded to include the droppings of bats and even seals.

Island with sea birds with a structure to collect guano

Photo Credit: Shutterstock.

Bird and bat guano are both rich in nitrogen, phosphate, and potassium, which are essential nutrients for plant growth. This is why guano has been used as a natural fertilizer for centuries, particularly in South America.

However, in the context of pest control, guano can present a problem. Accumulations of bat guano in attics, for example, can lead to health problems due to the growth of fungus that produces airborne spores.

These spores can cause a lung infection known as histoplasmosis, which can be severe, especially in people with compromised immune systems.

What is Guano Used For?

Guano is a highly valued commodity in certain sectors, particularly in agriculture. Derived from the excrement of seabirds, bats, and seals, guano is rich in nitrogen, phosphate, and potassium – three nutrients that are essential for plant growth.

In the realm of agriculture, guano is most commonly used as a natural fertilizer. With its high nutrient content, it provides an excellent, eco-friendly alternative to synthetic fertilizers.

Farmers and gardeners alike have been using guano for centuries to enrich their soil and boost crop yield.

The nitrogen in guano aids in leaf and stem growth, the phosphate is crucial for root development and blooming, while the potassium helps in the overall functioning of the plant.

Bat guano on a glass bowl with leaves on the table

Photo Credit: Shutterstock.

In addition to its use in agriculture, guano also has a significant role in ecological restoration. It is used to rejuvenate nutrient-depleted soils and restore the natural balance of ecosystems. This is particularly important in areas where intensive farming or deforestation has led to soil degradation.

Moreover, guano has also found its place in the production of gunpowder. The high nitrate content makes it a valuable ingredient in this process. However, this use is less common today due to the availability of synthetic alternatives.

History of Using Guano as Fertilizer

The history of using guano as a fertilizer is as fascinating as it is long. Guano, derived from the Quechua word ‘wanu’, is a term used to describe the accumulated excrement of seabirds, bats, and seals. This natural product has been used as a fertilizer for centuries, with its use dating back to the ancient civilizations of South America.

The Inca civilization, in particular, recognized the value of guano as a potent fertilizer. They collected it from the islands and coastal regions of Peru, where seabirds had been depositing their droppings for thousands of years.

The Incas had strict laws governing the collection and use of guano, understanding its ability to rejuvenate their agricultural lands and boost crop yields.

In the 19th century, guano became a highly sought-after commodity worldwide, leading to what is often referred to as the ‘Guano Age.’ European and North American farmers learned of its incredible fertilization properties and began importing it in large quantities.

The high demand for guano led to the Guano Islands Act of 1856 in the United States, allowing U.S. citizens to take possession of unclaimed islands containing guano deposits.

The use of guano as a fertilizer declined in the 20th century with the invention of synthetic fertilizers. However, in recent years, there has been a renewed interest in guano due to its organic nature and the increasing demand for sustainable farming practices.

Today, guano is still used in many parts of the world as a natural, eco-friendly fertilizer that enriches the soil and promotes plant growth.

Hand holding bat guano for fertilizer

Photo Credit: Shutterstock.

Which Country is Known to Have the Best Guano?

Among the many countries that produce guano, Peru is often cited as having the best quality. This is largely due to the country’s unique geographical and climatic conditions.

Peru’s coastal islands are home to large colonies of seabirds, including the Peruvian Pelican, the Guanay Cormorant, and the Peruvian Booby. These birds feed on the rich marine life off the Peruvian coast and their droppings, or guano, accumulate on the islands.

What sets Peruvian guano apart is the arid climate of these coastal regions. The lack of rainfall means that the guano is not washed away and can accumulate over time, often to a depth of several meters. This allows it to mature and concentrate, resulting in a product that is rich in nutrients.

Furthermore, the lack of rainfall also means that the nutrients in the guano are not leached out, which is a common problem in more humid climates. This results in a product that has a higher nutrient content compared to guano from other countries.

In addition to the ideal climate, the Peruvian government has also implemented strict regulations to ensure the sustainable harvesting of guano. This includes limiting the harvesting season and implementing measures to protect the bird populations.

How Guano Made Agriculture Boom

In the mid-19th century, the world experienced an agricultural revolution, and one of the key players in this transformation was guano. Its high concentrations of nitrogen, phosphorus, and potassium made it an excellent choice for boosting crop yields and enhancing soil fertility.

When guano was first introduced as a fertilizer, it was a game-changer. Farmers who had been struggling with depleted, unproductive soils suddenly found their fields flourishing with healthy, bountiful crops. The impact was so profound that it led to an agricultural boom, with crop yields increasing exponentially.

The effectiveness of guano as a fertilizer can be attributed to its unique composition. Nitrogen promotes healthy leaf growth and is crucial for the process of photosynthesis.

Bat guano on the ground

Photo Credit: Shutterstock.

Phosphorus is essential for root development and aids in the transfer of energy within plants. Potassium helps with water regulation in plants and also enhances their resistance to diseases and pests.

As word of this ‘white gold’ spread, the demand for guano skyrocketed, leading to the ‘Guano Age.’ Countries with rich guano deposits, such as Peru, became the focus of international attention, with many nations vying for control of these valuable resources.

The use of guano as a fertilizer not only led to an increase in crop production but also played a significant role in supporting the growing global population. It allowed for the cultivation of more land and the production of more food, effectively supporting the expansion of human settlements.

Benefits of Using Guano

Guano, as we’ve previously discussed, is a powerful natural fertilizer that has been used for centuries to boost agricultural growth.

But what exactly are the benefits of using guano? Why should you consider incorporating it into your gardening or farming routine?

Let’s look into the many advantages this unique substance offers.

  • Rich in Nutrients: First and foremost, guano is rich in essential nutrients. It’s packed with nitrogen, phosphorus, and potassium, the three primary nutrients needed for plant growth. Nitrogen promotes healthy leaf and stem growth, phosphorus aids in root development and flowering, and potassium enhances overall plant health.
  • Improves Soil Structure: Guano also improves soil structure. It helps to loosen compacted soil, making it easier for plant roots to spread and access the nutrients they need. This also improves water retention, ensuring plants have an adequate supply of moisture.
  • Slow-Release: Another significant benefit of guano is its slow-release nature. Unlike synthetic fertilizers that can overload plants with nutrients and potentially cause damage, guano releases its nutrients slowly over time. This provides a steady supply of nourishment for plants, promoting sustained, healthy growth.
  • Environmentally Friendly: Guano is also beneficial for the environment. It’s a renewable resource, sourced from natural bat and bird droppings, and using it reduces dependence on synthetic fertilizers, which often involve environmentally harmful production processes.

Common Types of Guano

When it comes to guano, many people are surprised to learn that there are actually several different types.

The type of guano is primarily determined by the diet of the bird, bat, or seal that produces it. Each type has its own unique benefits and uses, making it a versatile resource for various industries.

Bat Guano

Bat guano on the ground

Photo Credit: Shutterstock.

Bat guano is perhaps the most well-known type of guano. It’s rich in nitrogen, which makes it an excellent natural fertilizer.

Bats primarily consume insects, so their guano is also high in chitin, a substance that helps to control nematodes and other soil-borne pests. This makes bat guano a favorite among organic gardeners.

Bird Guano

Bird guano

Photo Credit: Shutterstock.

Bird guano is another common type of guano. Depending on the bird’s diet, it can be high in nitrogen, phosphorus, and potassium – all essential nutrients for plant growth.

Seabird guano, in particular, is renowned for its high nutrient content due to the birds’ fish-based diet.

Seal Guano

Seal guano is less common but still valuable. Seals primarily consume fish, so their guano is high in nutrients like nitrogen and phosphorus. However, it’s also high in salt content, which can be detrimental to some plants if not properly processed.

Is Using Bat Guano Dangerous?

While guano, particularly bat guano, is a highly effective organic fertilizer, there are some potential risks and dangers associated with its use. It is important to handle bat guano with care due to the potential for disease transmission.

Bat guano can harbor a fungus known as Histoplasma capsulatum. When the guano is disturbed, microscopic fungal spores can become airborne and, if inhaled, can cause a lung disease known as histoplasmosis.

Symptoms of histoplasmosis can range from mild, flu-like symptoms to severe respiratory issues. It is particularly dangerous for individuals with weakened immune systems.

Woman with a flu holding a white mug

Photo Credit: Shutterstock.

Additionally, bat guano can harbor the rabies virus. Although transmission of rabies from guano to humans is extremely rare, it is still a concern.

To minimize these risks, it is recommended that you wear protective gear, including a mask and gloves, when handling bat guano. It is also advised to wet the guano down before disturbing it to reduce the amount of dust and spores that can become airborne.

Furthermore, it is important to source your guano from reputable suppliers who have taken steps to sterilize the guano and reduce the risk of disease transmission.

How To Use Guano For Plants

Step 1: Choose The Right Guano

Different types of guano have different nutrient profiles. Bat guano is generally high in nitrogen, which promotes leaf growth, while bird guano is high in phosphorus, which is good for flowering and fruiting plants. Choose the type of guano that suits your plants’ needs.

Step 2: Prepare The Guano

Guano can be used in several ways. It can be mixed directly into the soil, or it can be diluted in water and used as a liquid fertilizer.

If you’re using it as a soil amendment, use about 1 cup of guano for every 10 square feet of garden area. If you’re making a liquid fertilizer, dissolve about 1 tablespoon of guano in a gallon of water.

Guano fertilizer in the ground

Photo Credit: Shutterstock.

Step 3: Apply The Guano

When using guano as a soil amendment, mix it into the top 2-3 inches of soil. If you’re using it as a liquid fertilizer, water your plants with the guano solution once a week. Guano can also be used as a foliar spray. Just make sure to dilute it properly and spray it on the leaves early in the morning or late in the evening to avoid leaf burn.

Step 4: Monitor Your Plants

After applying guano, monitor your plants closely. You should see improved growth, color, and yield. If your plants show signs of nutrient burn, such as yellowing or browning leaves, reduce the amount of guano you’re using.

Remember, while guano is a fantastic natural fertilizer, it should be used responsibly. Overuse can lead to nutrient burn and can harm the environment. Always follow the recommended usage rates and adjust based on your plants’ response.

3 Best Guano to Purchase

When it comes to purchasing guano, it’s essential to consider the source, quality, and nutrient content. Here are my top three recommendations for the best guano to purchase:

1. Roots Organics Nitro Bat Guano

Roots Organics Nitro Bat Guano packaging

Roots Organics Nitro Bat Guano – Photo Credit: Amazon.

This product is a favorite among organic gardeners. Sourced from insect-eating bats, it is rich in nitrogen, making it an excellent choice for promoting vigorous growth in plants. The high nitrogen content also makes it ideal for leafy plants and heavy feeders.

2. Down To Earth Seabird Guano

Down To Earth Seabird Guano Box

Down To Earth Seabird Guano – Photo Credit: Amazon.

If you’re looking for a guano with a balanced nutrient profile, this is a great option. Derived from seabirds, it provides a good mix of nitrogen, phosphorus, and potassium. It’s also OMRI listed, meaning it’s approved for use in organic farming.

3. Sunleaves Jamaican Bat Guano

Sunleaves Jamaican Bat Guano container

Sunleaves Jamaican Bat Guano – Photo Credit: Amazon.

This product is known for its high phosphorus content, making it perfect for encouraging blooming and fruiting in plants. It’s sourced from Jamaican fruit bats and is completely natural and organic.




Subscribe TO win!
Subscribe to Our Newletter to get access to exclusive content and get entered into our Giveaways and Contests!
 Thank you for visiting. By continuing, you agree to our Terms of Service and Privacy Policy.
Get access to exclusive content and get entered into our Giveaways and Contests!
 Thank you for visiting. By continuing, you agree to our Terms of Service and Privacy Policy.