How do fertilizers contribute to the acidification of the soil

Nutrients out of the bag How to properly fertilize the leisure garden

The floor

In central Germany the soils are quite good. There are mainly heavy loamy soils here, they are rich in nutrients and also hold nutrients better than light soils with a lot of sand, which are mainly found in northern Germany. It is sufficient to add a little nitrogen to heavy soils. It is mainly contained in organic nitrogen fertilizers, i.e. in natural raw materials that come from agriculture or animal production. Horn shavings, feather meal or bone meal are part of it. They release the nitrogen very slowly. Chemically synthetic fertilizers, on the other hand, often work faster, but are now also offered with a protective cover so that the nutrients are released more slowly. A basic distinction is made between light, medium and heavy soils.

The right pH in the soil

The pH value describes the acidity in the soil. There are acidic, neutral and basic soils. Most cultivated garden soils are in the slightly acidic range, i.e. around pH 6. Most plants prefer this value.

‹7; neutral = 7; basic: ›7

Lime increases the pH value, loosens the soil and releases many nutrients. However, you shouldn't lime every year, says Jörg Krüger, otherwise the soil will become impoverished and completely drained. It is quite sufficient to lime the soil every three to four years. If you have too basic soil, you should mix the soil with acidic soil, for example with bog soil.

Lime makes fathers rich and sons poor.

old saying

Fertilize in moderation

If the soil is undersupplied, Jörg Krüger recommends organic universal fertilizer. They contain everything plants need to grow. Those who want to do without animal products can, for example, use purely vegetable universal fertilizers, such as sugar beet molasses or pomace residues from wine production. Fertilizing can be useful, especially where nutrients are extracted from the soil. Vegetables such as cabbage or potatoes are heavy eaters and absorb many nutrients from the soil. But even here it often helps to keep a crop rotation every year. The soil can recover in this way.

Much helps much does not make sense when it comes to fertilization. Over-fertilization of individual nutrients can lead to deficiencies in other nutrients. The heavy and medium-heavy soils in Central Germany are often oversupplied! Plants want to be optimally supplied, not maximally and not minimally!

Jörg Krüger / gardener

Many hobby gardeners overfertilize their plants. These are usually well taken care of by simply adding compost in combination with organic nitrogen fertilization. Anything the plant cannot absorb moves into the groundwater. One of the main problems is nitrogen. Over-fertilization ends with too much nitrate in the drinking water. The nitrate is converted into carcinogenic substances in the body.

The right time to fertilize

Plants should be fertilized when they start growing. Therefore, they should be supplied with nutrients in the spring from March. Those who plant new plants should put some fertilizer in the planting hole. A handful of horn shavings, for example, is suitable here. Five to eight weeks later you can add a little more fertilizer.

Fertilizer types

Organic universal fertilizer or chemical-synthetic fertilizer

Organic fertilizers consist of natural raw materials and are obtained from plants or by processing animal products. Nitrogen (N) is contained in horn shavings, horn meal, horn meal, bone meal or nettle liquid. Nettle manure is applied diluted 1:10. Compound fertilizer is obtained from sugar beet molasses, feather meal, bone meal, fermentation residues, horse manure or sheep wool.

The trend is towards ecological gardening. Nowadays one should do without chemical-synthetic fertilizers. However, they are used in agriculture, where in the end it is often only about the yield and not about environmental protection. Chemical-synthetic fertilizers are not for the hobby gardener, says Jörg Krieger. A high level of specialist knowledge is required for correct use. Organic fertilizers are more suitable for the hobby gardener.

Sulfuric acid ammonia (N), Epsom salt (Mg, S), superphosphate (Ph), Thomas flour (Ph, Ca), kainite (K, Cl), carbonate lime (Ca), quicklime (Ca) blue grain, universal fertilizer (N, P, K, trace elements)

Special fertilizers - briefly explained

Special fertilizers are a combination of various nutrients that are tailored to the needs of the respective plant species.

Fertilizers for flowering plants also contain phosphorus. But phosphorus is often sufficiently available in our soils, says the expert and recommends a normal universal fertilizer for flowering plants.

Fertilizer for lush green leaves

Fertilizers for green plants, for example box tree fertilizer, also contain magnesium. However, if the soil is supplied with too much phosphorus or potassium, the plant can no longer absorb magnesium or iron. An additional supply of magnesium does not make sense here. Instead, the plants, for example the lawn, should not be fertilized for two or three years. Only a soil analysis really helps here.

Fertilizer for fruits and vegetables

Above all, fruits and vegetables need potassium in order to produce fruit. The nutrient is contained in compost, for example. Jörg Krüger explains that those who regularly supply their beds with compost do not need an additional supply of fertilizer.