Brief History

Guano has been used as a fertilizer for hundreds of years. In the 19th century it became a hot commodity around the world. Farmers wanted it, countries got rich off of it and even fought wars over it. In the 1840’s, American ships mined dung off the coast of Peru and it quickly became the principle fertilizer of the United States. By 1856, the United States government passed the Guano Islands Act. This allowed any unclaimed or unoccupied island containing guano (or sometimes called ‘dung’) to be annexed and protected by the US Navy. However, the market quickly stalled. Despite being one of the best natural fertilizers available, demand quickly fell by the birth of artificial fertilizers… until organic gardening became relevant!

How to Use

Seabird or bat dung is easy to use. Remember ‘dung’ is just another word for guano. When applying as a fertilizer, the two most common practices are top dressing your soil or adding it to your water. I prefer to top dress my soil, but either way works. As a good rule of thumb, make sure to read the directions before applying. I hear all the time the term “super bloom” when referring to guano. This is partly true, but it also depends on the type of dung you purchase. For instance, a dung high in nitrogen is definitely not a super bloom. But dungs high in phosphorus definitely are. Double check the NPK ratio before purchasing. Nitrogen rich dungs should be applied during the vegetative state, whereas phosphorus dungs should be applied during flower.

Guano Tea Recipe for Flowering

• To create a perfect tea for flowering, start by adding one cup of your favorite phosphorus rich guano per gallon of non-chlorinated water. 
• Enhance your tea by adding additional ingredients such as fish emulsion, worm castings, humic acid, seaweed concentrate, unsulfured molasses and rock dust.
• Brew your tea with an air pump for at least 12 hours.

Seabird guano vs Bat guano

Today Guano is making a comeback among organic gardeners. This super fertilizer is great for replenishing your soil with essential nutrients and trace elements. Dungs also make wonderful compost tea’s. Today you can find two types of guano for sale: bat and seabird. Bat guano is found in caves all around the globe. Seabird dung can also be found all around the world. Peru is considered one of the worlds best seabird guano because the oceanic currents brings cold water from Antarctica. This combination of cold water and warm air creates a dry climate that prevents rainfall and is a perfect environment for preserving.

Where to Buy Seabird Guano

There are several different brands that sell Peruvian Dung. Here are a few:

1. Buried Treasure Peruvian Seabird dung (12-10-3) contains nitrogen, potassium and phosphorus. This Seabird dung will enhance growth & plant vigor. Great for indoor and outdoor use. Use with vegetables, herbs, flowers, and ornamentals. Buried Treasure is micronized for better solubility & delivery. Does not contain fillers.
2. Sunleaves® Peruvian Powdered dung (12-11-2) is a high quality, additive-free plant nutrition. Comes in powdered form for excellent water solubility. Also, perfect for compost teas and hydroponic applications. There’s nothing like it for accelerating growth—use this high-powered plant food indoors and out on houseplants, vegetables, ornamentals and fruit trees.
3. Down to Earth Seabird Dung is a high phosphorus blend (0-11-0) that dramatically increases both the amount and size of blooms throughout the flowering period for all indoor and outdoor plants. This organic fertilizer also greatly enhances beneficial bacterial activity in the soil. It also is water soluble, so it makes an excellent tea or foliar spray when filtered.
4. Roots Organics Sea Bird Granular is an excellent source of phosphate (0-12-0) and calcium. Carefully sifted and processed to make it easy to work with, Roots Organics Seabird Guano encourages vigorous growth and is fast acting for quick results. All of the Roots Organics guanos have been carefully sourced for quality and harvested with habitat friendly methods so you and your garden get performance with principles.

Where to Buy Bat Guano

Fruit eating bats produce a dung that is high in phosphorus. Whereas, insect eating bats produce a dung that is high in nitrogen. Bat dungs high in Phosphorus should be applied during the flowering stage. Bat dungs high in nitrogen should be applied during the vegetative growth stage. 

1. Down to Earth Organic Bat Guano Fertilizer is an all natural fertilizer with (7-3-1) formula. It is listed by OMRI for organic use and is a good fertilizer for early and mid season booster applications.
2. Growing Shade 100% Bat Guano (6-10-3) comes from a natural cave in deep tropical rain forest. I love this dung! In my opinion it is one of the best currently available. The (6-10-3) npk ratio makes this fertilizer the ideal mid and late season booster. 
3. Roots Organics Nitro Bat Guano (9-3-1) provides an excellent source of nitrogen, phosphorus, and calcium. Roots Organics Nitro Bat dung encourages vigorous growth and is fast acting for quick results.
4. Espoma BG1 Organic Bat Guano (10-3-1) is an all natural, dry plant food derived from wild insect-eating bats. Comprised of 100% organic ingredients with no fillers or sludge.