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Anyone who grows vegetables and fruit hopes for a rich harvest with aromatic tomatoes, cucumbers, potatoes and whatever else the kitchen garden has to offer. Dehner's phosphate potash fertilizer is intended for use in the kitchen garden. Its strong emphasis is on nutrients that are so important for flower and fruit development Phosphorus, potassium, magnesium and sulfur provide your fruit trees and vegetables with everything they need for strong growth and healthy fruit development to need. The fertilizer is finely granulated with a grain size of three to five millimeters, which is easy to dose and spread. To ensure that the plants are evenly supplied, the product also has a long-term effect of six to eight weeks.

The Green24 professional Phosphate fertilizer contains 20 percent phosphate and, as it is a special liquid concentrate, can be used for both root and leaf fertilization. The bottle contains 250 milliliters of concentrate, which has to be diluted with water to make 150 liters of finished liquid fertilizer. The nutrients are available to the plants very quickly, but the product has no long-term effects. For a balanced supply of nutrients, you can mix the P20 phosphate fertilizer with other one-component fertilizers from the manufacturer (e.g. B. N20, K20, F05 or M10) and put together your own liquid fertilizer.

This Phosphorus potassium fertilizer is the ideal addition to a flower fertilizer (e.g. B. for the Bloom Complex from the same manufacturer) and is intended to increase the bloom formation. In order to fertilize You can use the product especially if there is a lack of phosphorus or potassium, especially if you have a lot of flowering ornamental plants such as roses or wisteria. This fertilizer is also a concentrate that you have to dilute with water before use. According to the manufacturer's instructions, an amount of 25 milliliters is sufficient for 10 liters of water, so that with the purchase of the 1-liter bottle you ultimately get 400 liters of ready-to-use liquid fertilizer.

Purchase criteria

scope of application

Together with nitrogen and potassium, phosphorus is one of the three main nutrients that are indispensable for the healthy growth of every plant and therefore in every NPK or Complete fertilizer are included. Flowering and useful plants in particular have a high need for this nutrient, which is why the Phosphorus content in fertilizers for flowering or vegetable plants as well as for fruit trees is basically something is higher. Not every phosphorus-based fertilizer is suitable for vegetables and fruits, so choose a product that is specifically intended for this application.

Fertilizer form

Solid fertilizer: Celebrations Phosphorus fertilizer are mostly available in granulate form. Granulated fertilizers have the advantage that they are applied immediately and do not have to be diluted first. Dosing is easy using the dosing aid supplied with many products, and it has to be Granules are only lightly worked into the root area of ​​the plant and then poured vigorously will. In addition, fertilizer granules do not point or dust, which is also a practical advantage.

Liquid fertilizer: Liquid phosphorus fertilizers, on the other hand, are concentrates that have to be diluted with water before use. For this reason, you get several hundred liters of ready-made liquid fertilizer from a 1 liter bottle. Liquid phosphorus fertilizers can also be used for both root and leaf fertilization, and you can fertilize and water with just one operation. Another advantage is that the nutrients are available to the plants more quickly.

Phosphorus species

There are several types of phosphorus that are used in fertilizers. The rock phosphorus required is usually obtained from deposits of marine life that are millions of years old (e. B. Mussels, snails, algae), as well as from the droppings of sea birds. Sea bird droppings, in turn, are also referred to as guano(€ 9.82 at Amazon *) known. Thomas flour, on the other hand, is produced as a waste product in the smelting of iron ore. This is often used as an inexpensive alternative to fertilizer, but it is heavily contaminated with heavy metals.

Phosphorus content

The phosphorus content varies greatly from product to product: Superphosphate contains about 18 percent of the nutrient, Phosphate potash between 8 and 15 percent, Thomas flour 8 percent and so-called P 20 liquid phosphate fertilizer a full 20 percent. The latter are only recommended for use in the event of a lack of phosphorus, which can be determined by taking a soil sample. Otherwise, NPK fertilizers with a slightly higher phosphorus content between 7 and 10 percent are perfectly adequate for use in vegetable and orchards.

Other nutrients contained

There are very few pure phosphorus fertilizers, as the nutrient is used almost exclusively in multi-component fertilizers. This makes sense if only because plants not only need phosphorus and a phosphorus deficiency also occurs very rarely. Instead, phosphorus-based multi-component fertilizers (especially PK fertilizers) or corresponding complete fertilizers are suitable for the flowering and kitchen garden. In connection with phosphorus, the nutrients nitrogen (N), potassium (K), sulfur (S) and magnesium (Mg) are important.

frequently asked Questions

How do I recognize a phosphorus deficiency?

Signs of a phosphorus deficiency can be, for example, (severely) reduced growth, little or even lack of abundance of flowers, lack of bud formation, susceptibility of the plant in question to diseases and Pest infestation. However, these symptoms can also have other causes, which is why a phosphorus deficiency is actually only about one Soil analysis can be determined.

Why is Thomas flour problematic?

Thomas flour, also known as Thomaskali, is a waste product from the smelting of iron ore. Because of this, it is heavily contaminated with heavy metals, which, when used as fertilizer, get into the soil and thus possibly also into the groundwater or get into fruit and vegetables. Chromium in particular is a problem here.

When do you apply phosphorus fertilizers?

When she Phosphorus fertilizer best to apply depends on the Phosphorus species away. Granulated fertilizers based on water-soluble types of phosphorus are quickly available to the plants and can therefore be spread in spring. However, if rock phosphates were primarily used in production, it is recommended that they be applied in autumn. Liquid phosphate fertilizers, on the other hand, can be used throughout the growing season.

Do you even need special phosphorus fertilizers in the garden?

Unless the supposed phosphorus deficiency (the signs of which on the plants can have many other causes) is not caused by a professional soil sample has been confirmed, fertilization with phosphorus-based fertilizers is not necessary. Many of these specialty fertilizers contain too many pollutants or pollute the environment by breaking down than yours Garden soil and do something good for your plants with the application.

Are there alternatives to artificial phosphorus fertilizers?

Instead, it is much better to use natural phosphorus-containing - and therefore unproblematic - sources for garden fertilization. Poultry manure (e.g. poultry manure) is particularly valuable. B. Pigeon or chicken manure), which should only be used when it has rotted well. Others too Manurefrom cattle or horses, for example, is rich in valuable plant nutrients, as is garden compost.

equipment

Chicken manure pellets

Well, you don't necessarily have to keep chickens yourself to get the benefits of manure. This natural fertilizer is also already well-composted in a practical and easy-to-dose pellet form. Simply sprinkle the pellets into the root area of ​​the plants to be fertilized, work them lightly into the soil and then pour them vigorously.

pH soil test

Before you apply a phosphorus fertilizer in the garden, it is useful to test the pH value. Phosphorus fertilizer is only available to plants when the acidity level is between 6 and 7, whereas the plants cannot utilize the nutrients when the pH value is acidic. You can use practical test sticks to test the pH value before fertilizing and then lime if necessary.