Guano is eagerly advertised as an additive in fertilizers. But what exactly is guano and what does it do for the plants?
Behind the melodic-sounding name "Guano" hides a long-known fertilizer made from animal dung, over which wars have even been fought. This is particularly popular because of its high nitrogen and phosphorus content. The origins of guano are in South America. This fertilizer did not reach Europe until the beginning of the 19th century. We have compiled more about guano fertilizers for you below.
Guano is often touted as a biological super fertilizer, but unfortunately that doesn't quite correspond to reality. Find out everything you need to know about guano and how it works as a fertilizer here.
What is guano anyway?
Guano is simply droppings from different animals. Guano was first discovered in the areas around the west coast of South America (Chile, Peru) and came from seabirds such as pelicans and cormorants.
Origins and Properties of Guano
The first samples of guano found their way from Peru to Europe as early as 1804. Alexander von Humboldt carried out the first chemical investigations of guano in Paris. The first major shipments of guano arrived in Britain in 1840 and made their way to Germany for the first time in 1841. But this fertilizer has an eventful history behind it: there were even wars over regions with high guano deposits in South America. Although the fertilizer was fiercely contested at first, demand dropped with the invention of the Haber-Bosch process.
Because this process made it possible to extract nitrogen from the air and use it as fertilizer. As a result, the demand for fertilizers from South America fell. Before us Europeans, however, the Incas had already discovered that this bird droppings can be used as fertilizer and thus increased the yield on their fields. However, the Incas mined this substance with a sustainable thought. They only took as much guano as could be regenerated - in contrast to later commercial miningof bird droppings, which seriously upset the balance of this ecosystem.
Disadvantages of Guano
The environment of the guano areas has been badly damaged by its mining. There were even two wars fought over this raw material, which went down in history as the Spanish-South American War and the S altpeter War. The coasts served as breeding grounds for these animals, which led to the accumulation of meter-thick layers of excrement. This droppings were then broken down as fertilizer and shipped to Europe. As a result, especially the penguins there suffered greatly. The penguins dig their nesting holes in the guano and they lost their nesting places due to the commercial exploitation of guano. This caused severe damage to the animal population. This irresponsible guano mining has severely damaged the ecosystem. The transport of guano across half the globe is also not very sustainable. The working conditions of the local guano miners are also often described as inhumane. So it becomes clear that guano is very stressful for nature and not necessarily resource-saving. It is therefore better to rely on locally produced, primarily organic fertilizers that have less impact on the environment - such as our Plantura organic fertilizers.
Guano from bats
There is also guano produced by bats. Compared to bird guano, however, the yield of a bat colony is rather low. Other problems are the management and mining of bat guano, because the caves are usually not very easy to reach. However, if you have bats in your attic, rejoice in the free fertilizer that accumulates there.
Guano as fertilizer
Regarding the composition, a distinction must be made between red and white guano. The red guano is fossil and has a phosphoric acid content of 20 to 30% because it is much older than the guano that occurs every day. It is used as an organic fertilizer and is often used in organic farming as a phosphorus fertilizer. The white guano, on the other hand, is the faeces produced by the animals every day and has a nutrient composition of 10 to 12% nitrogen, 10 to 12% phosphorus and up to 3% potassium. The nutrient composition of the fertilizer varies depending on the animal species that produces the guano. The differences in the NPK ratio (i.e. in the nitrogen-potassium-phosphorus ratio) can be clearly seen:
- Bat guano (nitrogen emphasized): 10 - 3 -1
- Bat guano (phosphorous): 3 - 10 - 1
- Seabird Guano (nitrogen-heavy): 12 - 8 - 1
- Seabird guano (phosphorous): 1 - 10 - 1
Apply Guano Fertilizer
Now you've learned a little about the origin and composition of guano fertilizer, but how do you use this fertilizer? Of course, the correct application depends on the form in which your fertilizer is. Guano is available as a powder or granules, as a liquid fertilizer and there are even fertilizer sticks that contain guano.
Most of the time, however, guano is found in organic fertilizers as an admixture to increase nitrogen and phosphorus levels. Due to the guano, the fertilizers have a higher nutrient content. However, you can also simply use primarily organic fertilizers with a long-term effect without guano, such as our Plantura organic universal fertilizer.
How to use guano fertilizer?
If you use guano in solid form, you should always work the fertilizer into the soil. After application, it is advisable to water the soil properly. Another promising method is the immediate introduction when planting. When planting out, simply add a teaspoonful of guano fertilizer to the planting hole. This means that the fertilizer is exactly where it is needed - at the roots of your plants. Liquid guano fertilizers are usually mixed with the irrigation water. Pay attention to the application instructions of the respective product. Fertilizer sticks with guano are already on the market and they impress with their ease of use. You simply take a stick from the pack, stick it into the ground a few centimeters from the edge of the pot and the fertilization is done. These sticks release the fertilizer over a longer period of time. This saves you the constant re-fertilization, especially with balcony or potted plants. Guano fertilizer is generally used for all plants in the garden or in the house. It is best used from March to September.
Dosage of Guano Fertilizer
When dosing fertilizers, you should first and foremost always observe the product information. In principle, you can't go wrong with 40 g of solid guano fertilizer per m² in spring or before sowing. If necessary, you can fertilize again in summer with the same amount. One kilo of an organic fertilizer mixed with guano, which has a nutrient ratio of 7 - 3 - 4, is sufficient for about 33 m³ of soil. Thatcorresponds to a fertilizer quantity of about 30 g per m³ soil.
For liquid fertilizers, simply dilute the fertilizer solution in the irrigation water. Before use, it is important to shake the bottle well so that the dregs dissolve and mix. You can often do the dosage with the lid, because there are notches for measuring the amount of fertilizer. For example, if you use a liquid guano fertilizer with an NPK ratio of 7 - 3 - 6, you should use the following dosages:
- For balcony and terrace plants you should use 10 to 15 ml of liquid fertilizer per liter of irrigation water once a week.
- For indoor plants, 5 ml of liquid fertilizer per liter of irrigation water once a week is sufficient. Depending on the type of plant, you need to fertilize much less frequently in winter.
When it comes to fertiliser, always remember that there are crops that require more nutrients and others that require less. That's why you should always read the manufacturer's information and check out our speci alty articles about your plants for their nutritional needs.
Buy Guano Fertilizer
Various fertilizers containing guano are available on the market. It is often advertised with the argument that this fertilizer is organic. It is of course true that the fertilizer consists of natural ingredients and does not contain any synthetically manufactured components. However, it is questionable whether it is biologically acceptable.
One should bear in mind that the seabird guano has come a long way before it ends up in our garden and that the degradation repeatedly interferes with an existing ecosystem. If sustainable gardening is important to you, why not try our Plantura organic fertilizers.
Is guano poisonous?
Ingesting fertilizer is generally not a good idea, but if you've inhaled guano fertilizer residue, it's definitely a good idea to get some fresh air. In the case of skin contact, it is sufficient to wash the area thoroughly with soap and water, and in the case of contact with the eyes, you should also rinse them thoroughly for 15 minutes. If you accidentally swallow the fertilizer, rinse your mouth out with water and then drink plenty of water. If you have come into contact with the fertilizer and feel unwell afterwards, you shouldalways consult a doctor.
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