The use of guano fertilizer was popular and widespread for a long time due to the valuable ingredients. But meanwhile the critical voices are increasing. Here we show what to look out for and why the drug can be dangerous.

What is guano?

The term was coined by the Inca, who used it to describe rotted bird droppings. So this is dung. This is mainly found at frequently frequented breeding and nesting sites . The original form is made from the droppings of seabirds such as pelicans and cormorants.

In the meantime, however, the metabolic end products of other animal species are also included. Seals and bats fall under this.

ingredients and benefits

The fertilizer contains important nutrients for plants. It refers to:

  • Potassium
  • calcium
  • Magnesium
  • Phosphor
  • nitrogen

The natural agent is therefore also traded as a complete fertilizer or NPK fertilizer.

Anyone who uses guano as a fertilizer can look forward to the following positive effects:

  • soil improvement
  • slow release of nutrients
  • natural fungicide
  • Correction of the pH value

Use guano correctly

Due to the high concentration of nutrients, extremely small amounts are sufficient. There is no general answer to the dosage, since all plants differ in their nutrient requirements.

Therefore, you should always pay attention to the information provided by the manufacturer. This applies to all commercially available forms. Because the special fertilizer is available in several consistencies.

dry form

In the dry form, guano fertilizer is ideal for repotting and long-term fertilization. It is available as:

  • granules
  • Pellets
  • powder

The following points are important in the application:

  • Distribute under the roots when transplanting
  • Incorporate thoroughly into soil if used for fertilization or dissolving in water
  • then water abundantly to avoid chemical burns on the roots
  • Work the agent well into the substrate and distribute evenly

liquid form

The fertilizer in liquid form can be easily added to the irrigation water. Five to ten milliliters per liter of irrigation water are usually sufficient. Again, follow the manufacturer’s instructions to avoid overdosing. How much is used and how often the fertilization takes place also depends on the respective plant.

Tip: Guano can also be an ingredient in other fertilizers. When choosing, you should therefore pay close attention to the composition.


While the high content of essential nutrients is a key advantage and has made guano fertilizer very popular, this fertilizer is not without disadvantages. These include, for example:

  • Degradation is a burden on the environment
  • Fertilizer made from bat droppings is often expensive
  • long transport routes are required for bird guano
  • Animals lose breeding grounds by extracting the manure

Note the different composition

In addition to the distinction between dry and liquid forms, there are also significant differences in the composition of guano and thus in the concentrations of the ingredients. The three main nutrients are nitrogen, phosphorus and potassium.

Plants have very different demands on the supply. For this reason, it makes sense to always choose the right fertilizer concentration.

Caution: toxic

Direct contact with fertilizers can, in some cases, have adverse health effects. This also applies to guano, which adds to the points of criticism. The agent is potentially toxic and corrosive to both humans and animals. Even skin contact can therefore lead to complaints.

Immediate measures are therefore required if the agent gets on the mucous membranes, in the eyes and airways or is swallowed.

safety instructions

When using guano fertilizer, you should take some safety measures.

This includes:

  • avoid direct contact
  • use gloves
  • Work the agent well into the soil or dilute it directly with water
  • Use dry fertilizer only on windless days
  • wear safety glasses

If, despite these preventive measures, there is contact or even ingestion of guano, the following points are important:

  1. thorough rinsing
  2. Drink plenty of water
  3. consult a doctor immediately in case of complaints
Note: This doesn’t just apply to humans. Even if pets have ingested the fertilizer, a veterinarian must be consulted. This can happen, for example, by licking their paws after playing in the garden or digging in the ground.

frequently asked Questions

Yes, in addition to the above benefits as a fertilizer, it is also said to improve taste.

Yes, there are special liquid fertilizers that are explicitly offered in stores for this purpose. The application recommendation can usually be found on the packaging.

No, although you use excrement here, the smell in fresh air is usually not perceived as disturbing.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *