A slow-release fertilizer makes fertilizing easier and more comfortable. But what makes the right long-term fertilizer? And when and how to use it?
Slow-release fertilizers, long-term fertilizers or depot fertilizers are fertilizers that have been specially developed for horticulture. Thanks to special mechanisms, these fertilizers have a long-lasting effect. But what distinguishes such long-term fertilizers and how do they work?
Long-acting fertilizers basically work with different mechanisms, which can extend the duration of the effect. You can find more about the mechanism of action and the properties of slow-release fertilizers below.
Effects and properties of organic slow-release fertilizers
Organic long-term fertilizers get their permanent effect from the fact that the nutrients are firmly bound. This means that the nutrients are not directly available to the plants and must first be broken down by microorganisms in order to become available to the plants. This breakdown by microorganisms is also dependent on the soil heat, moisture and soil air.
Of course, this digestion does not happen overnight, which is why organic fertilizers work slowly and gently. Due to this mode of action, which not only strengthens the plants but also actively promotes he althy soil life, organic slow-release fertilizers are a very good choice for your own home garden.
Effects and properties of mineral long-term fertilizers
In contrast, mineral slow-release fertilizers work with other mechanisms. These include coatings and slow-acting forms of nitrogen or stabilizers, which can significantly increase the duration of action. We will explain these mechanisms to you in more detail in the section on long-term mineral fertilizers. With many mineral fertilizers, the plants suddenly receive a large amount of nutrients and then have to wait again for the next application of fertilizer. There is also a risk that the nutrients will be washed out and lost in this way. Slow-release fertilizer includedNitrogen, phosphorus, potassium and often other nutrients such as magnesium, iron and small amounts of the equally important trace elements. They are perfectly matched to the plants.
Organic Slow Release Fertilizers
Organic fertilizers, the nutrients of which are organically bound, do not actually belong to the long-term fertilizers in the narrowest sense. With this type of fertilizer, the release of the nutrients depends on the composition, the biological activity of the soil organisms and the amount applied. Moisture and temperature in the soil also have an influence. These factors also affect the soil organisms that break down the nutrients. Organic farm fertilizers include manure and liquid manure, while organic commercial fertilizers include horn shavings, guano and sheep's wool.
The long-lasting effect is due to the fact that the nutrients in organic fertilizers cannot be absorbed directly by the plants, as is the case with many mineral fertilizers. The nutrients must first be broken down in order to become available to the plants. This results in a longer effect that is also milder. That is why they are suitable for the long-term supply of nutrients to the plants - such as our primarily organic Plantura organic fertilizers.
Mineral slow-release fertilizers
Mineral long-term fertilizers have a longer duration of action due to the mechanisms already mentioned. By means of special coatings and stabilizers, the fertilizers release their nutrient s alts relatively slowly and thus guarantee an effect for months. These nutrient s alts are immediately available to the plants after being released from the granules, only the release is slower.
Coatings
All fertilizers with "Cote" in their name have a lasting effect as they are coated with organic and biodegradable shells. In the middle are the water-soluble nutrient s alts that first have to penetrate this shell. The thicker the shell, the longer the effect of the slow-release fertilizer lasts, because the nutrient s alts only get through the shell slowly. It's also possible that the fertilizers get a coating of sulfur. Such a sulfur coating also slows down the release of nutrients and thus guarantees the prolonged effect of the fertilizer.
Nitrogen Shapes
Often become slow-flowingNitrogen forms used that guarantee a longer effect. Often these forms of nitrogen have poorer solubility or take longer to be converted by microorganisms.
The following forms of nitrogen are often used in slow-release fertilizers: urea-formaldehyde, CD-urea (crotonylidene diurea) or IB-urea (isobutylidene diurea).
Nitrogen Stabilizers
Stabilizers prevent the nitrogen from being mineralized too quickly - so the conversion of ammonium to nitrate is slowed down. This is achieved by inhibiting the Nitrosomonas bacteria without harming them. Nitrosomonas cause the first step of nitrification, i.e. the conversion of organically bound nitrogen or ammonium to nitrate. Such stabilizers include DIDIN and ENSAN.
Summary slow-release fertilizer:
- The long-term effect of mineral slow-release fertilizers is guaranteed by mechanisms such as coatings and stabilizers
- Slow release of nutrients
- After the release, the nutrients are immediately available for the plants and do not have to be broken down as with organic slow-release fertilizers
- Granulated fertilizers can be applied easily
- Organic long-term fertilizers have a milder effect than mineral ones
- Organic slow-release fertilizers first have to be broken down by microorganisms, but are therefore better for soil he alth
- Long-term effects range from three months to one year
Use slow-release fertilizer: when, how & how much?
The effects of slow-release fertilizers vary greatly depending on the products used. The exact period of effectiveness of commercial fertilizers can usually be found on the packaging and the product description.
When to use slow-release fertilizer?
In principle, one cannot generally name a perfect time for fertilizing. This always depends on the fertilizer used and the amount of nutrients in the soil. In principle, of course, fertilizing in the spring is a good way to guarantee a good start to the garden year.
You can use a slow-release fertilizer from the beginning of the vegetation period, even as early as February (when the soil has thawed). So your plants can go with youstart into the vegetation with full force and are optimally cared for during their development. Depending on the duration of the effect of your long-term fertilizer, one application in spring is sufficient. But it may also be that you have to use the fertilizer again, for example if the effect is only limited to three months. It can be used from spring to late summer.
How long does slow-release fertilizer work?
The duration of action of such a long-term fertilizer differs significantly. Slow-release fertilizers can last anywhere from three months to a year, depending on the suppliers and the products used. Information on this can be found on the product packaging, but note that the duration is mostly calculated for days with 21 °C. This means that a fertilizer with the effect of three months will be consumed and decomposed more quickly at temperatures above 21°C - consequently the duration of action will be shorter.
Here is a brief overview of the duration of action of different long-term fertilizers:
- Slow-release fertilizers with sheep's wool work for around five months
- Osmocote fertilizers work for up to six months
- Slow-release fertilizers with horn shavings work for at least three months
- Mineral long-term fertilizers work for a period of between three and six months
How to apply slow release fertilizer?
The depot fertilizers do not differ in application from other mineral fertilizers. You should apply it evenly to the areas to be fertilized and work it in lightly. It is best to use long-term fertilizer for new plantings and simply add the fertilizer to the planting hole.
For flower boxes and potted plants, simply mix the slow-release fertilizer with the potting soil and then place the plants in the soil-fertilizer mixture.
Summary Apply Slow Release Fertilizer:
- Apply slow-release fertilizer evenly
- These fertilizers are particularly suitable for new plantings
- You simply mix the long-term fertilizer with the potting soil
- Our primarily organic Plantura organic fertilizers are an alternative to long-term mineral fertilizers
Slow-release fertilizer for conifers, lawns & Co.
There are many different plants in our gardens, which of course also have very different needs. There are also different products with regard to long-term fertilization. Here we explain the basic differences between themContinuous fertilizers.
Slow release fertilizer for flowers
We expect our flowers to show their most beautiful blossoms for us. But this only works if they have enough nutrients to grow and develop properly. If you already use a long-term fertilizer when planting, you save yourself the trouble of fertilizing later. The long-term fertilizer is simply put into the soil at the beginning of the growing season and, depending on the duration of the effect, you should possibly fertilize again in the summer. Fertilizer sticks are also ideal for flower boxes as a long-lasting gift. Like conventional flower fertilizers, long-term flower fertilizers should contain nitrogen, phosphorus and potassium as well as trace nutrients such as calcium and magnesium for the green leaves. The need depends on the respective flowers and whether they are heavy or weak consumers.
Our Plantura organic flower fertilizer is an optimal alternative made from mostly organic raw materials. This flower fertilizer has an NPK ratio of 4 - 2 - 7 and optimally supplies your blooming darlings with nutrients. For flower boxes, for example, use 4 to 6 grams per liter of flower fertilizer before planting. For each additional fertilization we recommend applying 4 grams per liter.
Conifer slow release fertilizer
It is worth using long-term fertilizers, especially when planting new trees and shrubs. You simply put this in the planting hole so that the conifers are well supplied with nutrients while they are supposed to take root and start growing. But make sure that the conifer fertilizers contain magnesium in addition to nitrogen, phosphorus and potassium, because a lack of this nutrient often leads to the conifers turning brown. Then often only a treatment with Epsom s alt helps to compensate for the deficiency. In addition, the fertilizer used should also be low in chloride, because conifers are often sensitive to increased chloride levels.
Long-release potted plant fertilizer
Slow-release fertilizers are also particularly suitable for plants in pots or balcony boxes. When filling your pots, simply mix the slow-release fertilizer with your potting soil and place the plants in the substrate as usual. Another variant for long-lasting fertilization would be to use fertilizer sticks. You can find out more about the use of fertilizer sticks here in our special article. For potted plants, we recommend our Plantura organic universal fertilizer. For indoor plants use ata new planting simply 3 to 5 grams per liter of pot volume and your favorite potted plants are optimally cared for.
Lawn Slow Release Fertilizer
Especially for the lawn, a long-term effect is of great advantage, because it can prevent sudden growth and guarantee an even development of the lawn.
Long-term fertilization is exactly the right thing for this, because the nutrients are not released all at once, but continuously. This will give you optimal growth and you can enjoy your green spaces. If you are still looking for an organic autumn lawn fertilizer or organic lawn fertilizer, why not reach for our Plantura organic lawn fertilizers.