Make Your Own Organic Fertilizers – Natural Fertilizers for the Garden

Make Your Own Organic Fertilizers - Natural Fertilizers for the Garden

The advantages of organic fertilisers are obvious: natural fertilisers provide valuable nutrients, improve the soil in the long term and reduce the amount of waste. There is also hardly any fear of overfertilisation.

Make your own organic fertiliser for the garden


The most important recycled fertiliser is compost. It not only provides nutrients, but also sustainably supplies the garden soil with humus. Compost can be spread after one year of rotting.

If it is left to rot for longer, its fertilising effect decreases somewhat. On the other hand, it contains more permanent humus, which improves the soil over the years. As raw humus, it can be applied to the vegetable garden or to growing beds and buried. In half-soiled form, it is used as a late-winter gift for herbaceous borders and woody plants. Compost can be used as the sole fertiliser for plants with a low nitrogen requirement (for example, many herbs, radishes, peas).

If you do not have much space, you can also set up a worm bin indoors. Compost worms, which can be purchased commercially, eat the organic kitchen waste – and this produces the valuable worm compost.

Plant slurry

Plant slurries are particularly rich in nitrogen. They work faster than compost and can also be produced much more quickly. To make it, ferment about one kilo of green plants such as comfrey, lungwort, nettles or green manure plants in ten litres of water for two to three weeks, strain and dilute with ten parts of water. Water weekly with it. This is how easy it is to make your own organic fertiliser.


With the help of Effective Microorganisms (EM) you can produce a high-quality fertiliser and do not need much space. EM are a mixture of lactic acid bacteria, photosynthetic bacteria and yeasts. The so-called Bokashi bucket is an airtight container with a sieve insert into which organic waste is filled. The organic source material is sprayed with Effective Microorganisms and then takes some time to ferment. Rock flour helps to make the released nutrients more available to the soil.

If you have a lot of lawn clippings, you can put them in a plastic bag and add an EM solution to the material. Then tie the bag shut and leave it in a shady corner of the garden for a fortnight. This is another way to make a high-quality natural fertiliser that can also be buried in the soil.
Other natural fertilisers for the garden

Coffee grounds

Coffee grounds are a nitrogen-rich biofertiliser that also contains a little phosphorus and sulphur. Coffee grounds have a positive effect on the humus content in the soil and also slightly lower the soil pH due to its humic acid content. For this reason, it is ideally suited for acid-loving plants such as rhododendrons, hydrangeas and blueberries.

Coffee grounds should only be used in the garden and should always be lightly worked into the soil – only then will they decompose well and develop their fertilising effect. However, cold brewed coffee can also be used to fertilise indoor and potted plants. Dilution with water in a 1:1 ratio is recommended.


Eggshells are an excellent lime fertiliser. They provide plenty of calcium carbonate, which can raise the pH of a soil. In addition to calcium, they also contain small amounts of potassium, phosphorus and magnesium. For application, it is recommended to crush the eggshells and add water.

Dung and manure as natural fertiliser

Manure is an excellent biofertiliser. It provides valuable nutrients for plants as well as structural material for the soil. Manure and dung from cows, horses, sheep and chickens can be worked into the soil in small quantities (3 kilograms per square metre) before cultivation begins.

The fertilising effect lasts for a long time: Over a period of three years, the manure continuously releases its nutrients – but in the first year it shows the greatest effect. In the case of highly productive plants, additional nitrogen, for example in the form of horn shavings, must be applied in the second or third year.

The manure should be stored for at least six months, horse manure for one year is best. Ideally, it is mixed with other organic material such as grass cuttings and leaves and composted together. During storage, potential pathogens from the animals’ excretions are also killed.

As a general rule, manure should not be stored for more than one year, as the nutrient content gradually decreases. It is only worked flat into the soil so that it can rot well with the help of oxygen.

Urine is also a good fertiliser, containing nitrogen, potassium, calcium and phosphorus. The nitrogen is mainly in the form of urea. If it is strongly diluted with water – in a ratio of 1:10 for strong growers and 1:20 for weak growers – it can be spread on beds.

Sheep’s wool

Sheep’s wool is a complex fertiliser. It contains nitrogen, potassium and sulphur as well as small amounts of phosphate and magnesium. If the wool (often available as dirty wool) is plucked apart into small flakes, it can be spread over a large area on the bed and covered with a layer of soil. For. Tomatoes or planting potatoes, the wool can be added directly to the planting hole.

Wood ash

Ash from untreated wood is a potassium-rich natural fertiliser that celery and potatoes, for example, appreciate. However, it also contains lime and often heavy metals. So it should be used with caution and not lime at the same time. The ashes of barbecue charcoal are not suitable for the garden area – burnt residues can contain substances that are harmful to health.