NPK fertilizer: composition, application and benefits

The NPK fertilizer; For many a mystery, for experienced gardeners essential nutrients for healthy plants. Also known as complete fertilizer, this form of fertilizer is one of the complex fertilizers and has different ingredients, the composition of which differs from plant species to plant species can. They work effectively for garden or house plants and in the greenhouse, which makes them essential once properly applied, which effectively limits possible disadvantages.

composition

NPK fertilizers are special fertilizers whose concept came up in 1927 by the German chemical company BASF SE from Ludwigshafen am Rhein with the product Nitrophoska. The goal of these fertilizers was to provide the necessary core nutrients for plants in a concentrate that was easy to administer. The three main components of NPK fertilizers not only define the composition, but also gave the fertilizer its name. These are the ones listed below.

Nitrogen (N)

Nitrogen is one of the most important substances for plants of all kinds, as it is essential for the metabolism and growth of plants. Nitrogen enables basic processes within the plant, such as the formation of shoots, leaves and flowers, and is just as important for the general vitality of the plants. The following problems arise when there is not enough nitrogen.

• Chlorophyll cannot be formed sufficiently
• this in turn leads to pale plant parts and metabolic problems
• the formation of vital vitamins and proteins is made more difficult
• Stunted stature is possible
• Side shoots and shoots are only sparsely developed
• vegetative and generative parts of plants are usually made smaller
• Leaves often turn yellow
• if the deficiency is too high, the leaves dry out and the leaves are lost
• Fruits are only sparsely developed
• this affects both the yield and the quality of the fruit
• if the deficiency is not remedied, the plant may perish

With all fertilizers, however, it should be noted that the amount required for the respective plant species must not be too low or too high.

Too much nitrogen can lead to the following complications:

• too fast growth
• thin leaves and shoots
• powerless growth

Phosphorus (P)

In comparison to nitrogen, phosphorus is used for the formation of strong roots, fruits and flowers and can be restricted by too much nitrogen. In addition, phosphorus drives photosynthesis, which is essential for all plants. Another advantage of the substance is the beneficial effect on winter and frost hardiness. Plants that need a lot of phosphorus, such as fir trees, can easily survive the winter thanks to the fabric. Phosphorus is also used for germination, as the substance provides the necessary energy for this. The symptoms of phosphorus deficiency are as follows.

• The ripening of fruits is slowed down, sometimes completely restricted
• Fruits are only sparsely developed
• Roots grow weak, brittle or not deep enough
• all growth is delayed
• also has a negative effect on the quality of the fruit
• Leaf margins turn blue, green, blue-green, red, red-violet
• Discoloration later spreads to the entire leaf

Too much phosphorus in mineral fertilizers leads to chlorosis, a plant disease that restricts or completely prevents the use and formation of chlorophyll.

Potassium (K)

Potassium is the third substance in the league and essential for water absorption and water balance, as well as resistance to diseases, fungi and viruses. In addition, potassium promotes the vitality of the plant parts and resistance to extreme weather such as droughts and permafrost.

A potassium deficiency shows up immediately with the following symptoms:

• Fruits, buds and flowers are less developed
• Plant parts appear limp because the cell walls are not strong enough
• fewer roots are formed
• Leaf margins turn brownish
• Leaf margins and tips look burned
• less water is absorbed

However, the dosage of potassium can also be increased, which leads to the following problems.

• The substrate is salinated
• Minerals like magnesium can no longer be absorbed

Together, these three substances make up the so-called NPK value, which is recorded on the packaging of the NPK fertilizer. The NPK value shows what the mixing ratio of the ingredients, i.e. the fertilizer composition, is. The amount of the substance contained is given in three numbers, each representing the percentage of nutrients in the total mixture.

Two examples:

• NPK fertilizer for Green plants: 14-20-8 (composition of 14% N, 8% P, 20% K)
• NPK fertilizer for Flowering plants: 7-6-8 (composition of 7% N, 8% P, 6% K)

As you can see, the green plants generally need more potassium and nitrogen, while flowering plants need sufficient phosphorus. In addition to these substances, it also contains other nutrients that the plant needs for numerous processes.

• calcium
• magnesium
• sulfur
• Trace elements, including zinc, iron, copper and numerous other nutrients

The more specialized the fertilizer is for a type of plant, the more different the compositions can be. However, the additional nutrients are rarely recorded in their direct amounts.

They are made in the following forms:

• fluid: mostly for the home area, especially indoor and container plants
• solid (granules in different sizes): mostly used for gardens and larger areas, has a long-term effect

Of course, the fertilizers can be used for any form of husbandry, but the correct granulate size should be selected for solid fertilizers.

In addition, the NPK fertilizers are offered in three variants:

• mineral
• mineral-organic
• organic

Depending on the type of plant, attention should also be paid to this point, as not every plant can tolerate organic or mineral fertilizers.

Please note: Depending on the manufacturer, the individual numbers can be mixed up. While an NKP fertilizer is the same as an NPK fertilizer, you should pay attention to the order in which it is used the respective substances are listed so that you do not accidentally add the potassium to the phosphorus confound.

use

The application of the NPK fertilizers has proven to be extremely uncomplicated, as they are available in a finished form and do not have to be mixed by yourself. When using it, there are only a few points to pay attention to in order to achieve the best possible fertilization performance.

To do this, proceed as follows:

• Time: Spring fertilize once to prepare for the vegetation phase
• NPK long-term fertilizers are usually re-fertilized once in midsummer
• with conventional variants, re-fertilize depending on the needs of the plant or the manufacturer's instructions
• last fertilization at the beginning of July so that the new shoots can sprout and do not freeze over the winter
• when fertilizing, follow the manufacturer's instructions regarding the amount
• alternatively, read the fertilizer instructions for the respective plant species
• Liquid fertilizer is administered via the irrigation water
• Spread NPK lawn fertilizer with a spreader, as this will make the distribution more even
• Granules are weighed out before distribution
• this will prevent over- or under-fertilization
• the granules are distributed in the soil around the plant
• You can easily start at the stem base
• however, do not damage the roots near the surface
• if the soil is dry, it must be poured immediately after the fertilizer has been applied
• this step is not necessary on rainy days

Tip: If you have roses, hibiscus, hydrangeas or buddleia, you can fertilize them with a calcium-based fertilizer (potash fertilizer) even later than July. This strengthens the winter hardiness of the plants and is particularly effective with these plants.

When using it, you should avoid the following mistakes:

• never apply the fertilizer to the leaves, flowers or roots
• this leads to acidification and potential death of the affected areas
• avoid days when the sun is particularly strong
• Here too, the sun's rays could lead to over-acidification
• likewise, the soil should never be bone dry
• do not over-fertilize; especially important for fertilizers on a mineral basis

advantages

Thanks to its ingredients and availability, the NPK fertilizer is one of the simplest and most effective fertilizer variants.

The following advantages should be mentioned:

• Basic care is covered
• Fruit yields increase visibly
• more and healthier flowers are formed
• Plants can use the fertilizer immediately
• this does not have to be converted by microorganisms or in any other way
• easy to use
• Nutrients are optimally matched to the needs of the crops
• also acts as a slow release fertilizer

disadvantage

The advantages predominate, but there are clear disadvantages that are noticeable when using NPK fertilizers.

• usually more expensive to buy
• significantly more energy is required for production, which can have a negative impact on the environment
• The chance of over-fertilization is quite high