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Patentkali is one of the most popular Potassium fertilizers. In addition to a high proportion of potassium, the product also contains sulfur and magnesium. Patentkali is offered as low-dust and easy-to-apply granules, which are simply sprinkled and then is vigorously watered - the fertilizer granules gradually dissolve on contact with water and then seep into the Floor a. According to customer reviews, this product takes a few days to fully dissolve. Patentkali is versatile and suitable for all types of soil and plant locations. It is also approved for use in organic farming.

This potassium fertilizer from Dehner contains a high proportion of potassium as well as phosphate, sulfur and magnesium. The product is available in low-dust granulate form, which you can simply apply to fertilizing Apply area - ten kilograms are sufficient for around 100 square meters, depending on the composition of the soil and vegetation. The advantage of this potassium fertilizer lies in the integrated long-term effect, whereby part of the rock phosphate contained can be immediately absorbed and used by the plants. The product is particularly suitable for the fertilization of useful plants, especially of strongly consuming vegetable plants as well as fruit and berry trees.

This potassium fertilizer from the manufacturer Beckmann also contains high levels of sulfur and magnesium and is therefore a valuable mineral fertilizer for many useful and ornamental plants. The low-dust granulate is low in chloride and is particularly suitable for chloride-sensitive plant species, which in addition to many fruit and vegetable plants also include sunflowers, grapevines and hops. The potassium fertilizer strengthens the plants and makes them less sensitive to various pathogens. In addition, the application increases the formation of flowers and fruits and thus increases the yield. The product is also suitable for treating an existing potassium deficiency.

Purchase criteria

Type of potassium fertilizer

There are several types of potassium fertilizers. The potassium content varies depending on the type, and various other nutrients - such as magnesium and sulfur - are added. Other products, on the other hand, are not pure potassium fertilizers, but multi-component fertilizers with an emphasis on potassium. Here we briefly introduce you to the most important species for use in the kitchen and ornamental garden.

Patent potash: Patentkali - also known as potash magnesia - contains not only potassium but also magnesium and sulfur. This potassium fertilizer is readily soluble in water so that the nutrients are quickly available to the plants. As a rule, patent potash is obtained from the naturally occurring mineral kieserite, which is why it is a natural product. Patentkali is low in chloride or chloride-free and is therefore also suitable for sensitive garden plants such as rhododendrons.

Thomaskali: Thomas or phosphorus potassium consists of the main components potassium and phosphorus, it also contains magnesium. This potassium fertilizer has a granular structure that is easy to apply in the garden. Thomaskali is a by-product of the production of steel or iron. Sometimes the fertilizer is also called Thomas flour.

Potassium sulfate: Potassium sulphate has a very high proportion of potassium and a similarly high proportion of sulfur. It is a fine to coarse-grained, white salt, which is very suitable for liquid fertilization. Since potassium sulfate, chemically the potassium salt of sulfuric acid, is also low in chloride, you can use it to fertilize sensitive plants - such as raspberries or blackberries.

Autumn potassium fertilizer: In addition to the potassium fertilizers presented, there are a number of autumn fertilizers, most of which are multi-component fertilizers with a greater or lesser emphasis on potassium. The strong emphasis on potassium in fertilizers administered in autumn is explained by the anti-freeze effect of potassium, which protects plants from damage in winter.

Potassium lawn fertilizer: Even with potassium-accentuated Lawn fertilizers It is a special autumn fertilizer that is tailored to the needs of the lawn grass and is intended to protect the green area from frost damage in winter.

Fertilizer form

Solid fertilizer / granules: Potassium fertilizers are mostly available in granulate form, which are particularly easy to apply. The fertilizer granulate is simply spread over the intended area - you should absolutely refer to the manufacturer's instructions for Keep the dosage, because over-fertilization can have serious consequences - and it dissolves slowly after repeated vigorous watering on.

Liquid fertilizer: The use of a liquid potassium fertilizer makes sense if the nutrient should or must be available to the plants as quickly as possible. Liquid fertilizer is given together with the irrigation water and immediately seeps into the roots.

Grit

Fertilizer granulate is available in different grain sizes. Potassium fertilizers can therefore be selected from fine to coarse grains, whereby other factors play a role in addition to the intended area of ​​application. The finer the grain, the faster it dissolves and seeps into the ground - but the more likely it is to get dusty and fly away with the wind.

Quantity / packaging

Whether you choose a sack of 50, 25 or 5 kilograms of potassium fertilizer depends on how large the area to be fertilized is. Basically, you can supply around 100 square meters of garden with ten kilograms of fertilizer, although this figure is of course an estimate. This can be higher or lower, depending on which plants you want to fertilize - some species need more potassium than others. For lawn, you should plan around 50 to 70 grams per square meter.

frequently asked Questions

What is Potassium

Potassium is a natural chemical that occurs in every soil - but mostly in bound form, which is why it is only available to plants to a limited extent. Potassium is also naturally present in plants, but it is used up with the age and growth of the plant and cannot be regenerated by it.

What do you need a special potassium fertilizer for?

When the natural potassium stores in the plants run out, older leaves and shoots eventually die off. An additional supply of the nutrient ensures that the plants stay healthy and strong, grow better and can also defend themselves against diseases and pests.

In which areas of the garden does it make sense to use potassium fertilizer?

Potassium fertilizer is particularly often used for the autumn fertilization of lawns. But also in Kitchen and ornamental garden it makes sense to use it, for example to make shrubs and other woody plants winter-proof. After all, woody plants in particular need a lot of potassium, as do some crops. The latter should with the administration of potassium against diseases like the Flower end rot protected, and potassium fertilization increases the yield.

What types of potassium fertilizers are there?

Pure one-component potassium fertilizers are hardly available; most potassium fertilizers are mixtures of two or three nutrient elements or a multi-component fertilizer with an emphasis on potassium. In addition, additional ingredients can be added to the fertilizer, for example Weed and moss killers. The latter are intended for fertilizing lawns.

How do you recognize a potassium deficiency?

A potassium deficiency is particularly evident in older plants as well as on sandy or calcareous soils. Affected plants are very susceptible to diseases and pests, grow poorly and old shoots suddenly die off. In fruit trees, ripe fruits do not have the desired aroma, and flower end rot occurs more frequently. Leaves yellow and typically have a brown, necrotic leaf margin.

Can too much potassium be harmful too?

Be sure to follow the manufacturer's fertilization recommendations, as over-fertilization with potassium can over-acidify the soil. As a result, the plants no longer absorb other important nutrients in sufficient quantities, as well An excess of potassium leads to damage to the roots and can eventually kill the plant cause.