Along with nitrogen and potassium, phosphorus is one of the three main nutrients in plants and is contained in every NPK fertilizer. Flowering and useful plants in particular have a higher need for phosphorus, which is why a phosphorus fertilizer can be useful for these species. However, pure phosphorus fertilizers are not advisable in home and hobby gardens, it is better to use phosphorus-rich multi-component fertilizers instead.
Phosphorus is one of the main nutrients in plants
Our recommendations
our recommendation
Dehner phosphate potash fertilizer with long-term effect, 10 kg, for approx. 100 sqm
13.99 EUR To the product| quantity / packaging | 10 kilograms |
|---|---|
| Enough for | about 100 square meters |
| fertilizer type | mineral |
| fertilizer form | solid, granules |
| phosphorus content | 10 percent |
| More nutrients | Potassium 15 percent, magnesium 5 percent, sulfur 12 percent |
| Price/m² | approx. EUR {PRICE/100} |
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. The Dehner phosphate potash fertilizer is intended for use in the kitchen garden. Its strong emphasis on nutrients such as phosphorus, potassium, magnesium and sulfur that are important for flower and fruit development provides your fruit trees and vegetable plants with everything they need for vigorous growth and healthy fruit development . The fertilizer is finely granulated with a grain size of three to five millimeters, which is easy to dose and apply. To ensure that the plants are evenly supplied, the product also has a long-term effect of between six and eight weeks.
our recommendation
GREEN24 Purital P20 Supreme phosphate fertilizer HIGH-TECH phosphate liquid fertilizer
9.95 EUR To the product| quantity / packaging | 250 milliliters |
|---|---|
| Enough for | 150 liters of finished fertilizer |
| fertilizer type | mineral |
| fertilizer form | fluid |
| phosphorus content | 20 percent |
| More nutrients | k. A |
| Price/m² | about {PRICE/150} EUR |
The Green24 professional phosphate fertilizer contains 20 percent phosphate and, since it is a liquid special concentrate, can be used for both root and foliar fertilization. The bottle contains 250 milliliters of concentrate, which has to be diluted with water to make 150 liters of liquid fertiliser. The nutrients are available to the plants very quickly, but the product has no long-term effect. For a balanced supply of nutrients, you can mix the P20 phosphate fertilizer with other one-component fertilizers from the manufacturer (e.g. N20, K20, F05 or M10) and put together your own liquid fertilizer.
our recommendation
Hesi Phosphorus Plus, 1 l
13.49 EUR To the product| quantity / packaging | 1 liter |
|---|---|
| Enough for | 400 liters of finished liquid fertilizer |
| fertilizer type | mineral |
| fertilizer form | fluid |
| phosphorus content | 7.2 percent |
| More nutrients | Potassium 5 percent |
| Price/m² | about {PRICE/400} EUR |
This phosphorus-potassium fertilizer is the ideal addition to a bloom fertilizer (e.g. for the Bloom Complex from the same manufacturer) and is intended to strengthen bloom formation. You can use it to fertilize ornamental plants that bloom strongly, such as roses or wisteria, as needed, but you can also use the product if there is a lack of phosphorus or potassium. This fertilizer is also a concentrate that you have to dilute with water before use. According to the manufacturer, a quantity of 25 milliliters is sufficient for 10 liters of water, so that with the purchase of the 1-liter bottle you ultimately receive 400 liters of finished liquid fertilizer.
Purchase Criteria
scope of application
Along with nitrogen and potassium, phosphorus is one of the three main nutrients that are essential for the healthy growth of any plant and are therefore included in every NPK or compound fertilizer. Flowering and crop plants in particular have a high need for this nutrient, which is why the phosphorus content in fertilizers for flowering or vegetable plants and fruit trees is generally slightly higher. Not every phosphorus-based fertilizer is suitable for vegetables and fruit, so choose a product that is specifically designed for this application.
fertilizer form
solid fertilizer: Solid phosphorus fertilizers are mostly available in granular form. Granulated fertilizers have the advantage that they can be applied immediately and do not have to be diluted first. Dosing is easy with the dosing aid supplied with many products, and the granules only have to be worked lightly into the root area of the plant and then poured vigorously. Fertilizer granules also do not sharpen and dust, which is also a practical advantage.
liquid fertilizer: Liquid phosphorus fertilizers are concentrates that have to be diluted with water before use. For this reason, you get several hundred liters of finished liquid fertilizer from a 1-liter bottle. You can also use liquid phosphorus fertilizers for both root and foliar fertilization, and you can fertilize and water in just one operation. Another advantage is that the nutrients are available to the plants more quickly.
phosphorus type
There are different types of phosphorus used in fertilizers. In most cases, the raw phosphorus required is obtained from deposits of sea creatures (e.g. mussels, snails, algae) that are millions of years old, as well as from the droppings of seabirds. Sea bird droppings are also known as guano (€121.99). Thomas flour, in turn, is a by-product of iron ore smelting. This is often used as a cheap alternative as fertilizer, but is highly contaminated with heavy metals.
phosphorus content
The phosphorus content varies greatly from product to product: superphosphate contains 18 percent of the nutrient, phosphate potash between 8 and 15 percent, Thomas flour 8 percent and so-called P 20 liquid phosphate fertilizers a full 20 percent. The latter are only recommended for use in the event of a phosphorus deficiency, which can be determined by a soil sample. Otherwise, NPK fertilizers with a slightly higher phosphorus content of between 7 and 10 percent are completely sufficient for use in vegetable and orchards.
Other nutrients included
There are very few pure phosphorus fertilizers, as the nutrient is used almost exclusively in multi-component fertilizers. This makes sense because plants not only need phosphorus and a phosphorus deficiency only occurs very rarely. Instead, phosphorus-based multi-component fertilizers (especially PK fertilizers) or corresponding complete fertilizers are suitable for flowering and kitchen gardens. In connection with phosphorus, the nutrients nitrogen (N), potassium (K), sulfur (S) and magnesium (Mg) are important.
youtubefrequently asked Questions
How do I recognize a phosphorus deficiency?
Signs of a phosphorus deficiency can be, for example, (severely) reduced growth, few or even no flowers, lack of bud formation, susceptibility of the plant concerned to diseases and pest infestation. However, these symptoms can also have other causes, which is why a phosphorus deficiency can actually only be determined via a soil analysis.
Why is Thomas flour problematic?
Thomas flour, also known as Thomas potash, is a waste product from the smelting of iron ore. As a result, it is heavily contaminated with heavy metals, which, when used as fertilizer, get into the soil and thus possibly also into the groundwater or into fruit and vegetables. Chromium in particular is a problem here.
When do you apply phosphorus fertilizer?
The best time to apply phosphorus fertilizer depends on the type of phosphorus. Granulated fertilizers based on water-soluble phosphorus species are quickly available to the plants and can therefore be spread in spring. However, if rock phosphates were primarily used in the production, it is advisable to apply them 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?
If the supposed phosphorus deficiency (the signs of which can have many other causes on the plants) has not been confirmed by a professional soil test, fertilization with phosphorus-based fertilizers is not necessary. In addition, many of these special fertilizers contain too many pollutants or pollute the environment through degradation for you to do something good for your garden soil and your plants by using them.
Are there alternatives to artificial phosphorus fertilizers?
Instead, it is much better to use naturally phosphorus-containing - and therefore unproblematic - sources for garden fertilization. Poultry manure (e.g. pigeon or chicken manure) is particularly valuable, but it should only be used if it is well rotted. Other stable manure, such as from cattle or horses, is also rich in valuable plant nutrients, as is garden compost.
equipment
Chicken Manure Pellets
our recommendation
HaGaFe Chicken Manure Poultry Manure Chicken Manure Poultry Manure Garden Fertilizer Dung, 30kg (2x15kg)
To the productNow, you don't necessarily have to keep chickens yourself to reap the benefits of chicken manure. This natural fertilizer is also available already well composted in practical and easy-to-dose pellet form. Simply sprinkle the pellets in the root area of the plants to be fertilized, work them lightly into the soil and then water vigorously.
pH soil test
our recommendation
Neudorff pH soil test to determine the soil pH value of the lime requirement 8 tests in a set
8.98 EUR To the productBefore applying a phosphorus fertilizer in the garden, it makes sense to test the pH value. Phosphorus fertilizer is only available to plants at a neutral acidity of between 6 and 7, while plants cannot utilize the nutrient at an acidic pH. You can use practical test sticks to test the pH value before fertilizing and then lime if necessary.