What kind of plant is the 14th

Which fertilizer is suitable for which plant?

Status: March 9th, 2021 4:05 p.m.

Organic and mineral fertilizers, special fertilizers in liquid or solid form: the range is huge. An overview of the different plant fertilizers and their uses.

by Helge Masch

For plants to thrive, they need the right nutrients. An over- or undersupply leads to an increased susceptibility to diseases and to stunted growth. The right fertilizer strengthens the plants, existing damage can be repaired with fertilizer. Whenever you use fertilizers, it is important that the soil is moist. The frequency always depends on the information on the packaging.

Inorganic fertilizers are suitable when there is a lack of nutrients

Inorganic fertilizers (mineral fertilizers) are available to plants more quickly than organic fertilizers and can be used specifically when there is a lack of nutrients. The respective proportions of the individual nutrients vary in the products offered for sale. Important components are nitrogen (N), phosphorus (P) and potassium (K).

If fertilizers contain all three elements, they are called NPK fertilizers or complete fertilizers. There are also two and one nutrient fertilizers available. Depending on the composition, there are fertilizers that are quickly washed out of the soil, but there are also long-term fertilizers.

Organic fertilizers are not immediately available

Organic fertilizers such as compost, manure or horn shavings are more environmentally friendly because they consist of organic (animal or vegetable) waste products. Often, however, it is pure nitrogen or nitrogen-based fertilizers. However, complete fertilizers are also available on the market. Organic fertilizers are not directly available to plants, they first have to be broken down by microorganisms. The coarser the fertilizer, the longer it will take. Coarse fertilizer should therefore be applied as early as autumn.

NPK - The composition of Complete fertilizer

The composition of a complete fertilizer has an impact on the growth, health and abundance of flowers in plants. Each component has different functions and can lead to problems if there is an over- or under-supply.

N = nitrogen

This nutrient represents strength and growth. Plants love nitrogen and prefer to take it up.

  • Too little: The leaves are yellow or pale green - the growth is very little.
  • Optimal: The leaves are bright green, growth is normal to rapid.
  • Too much: The leaves become fattened, long and the tissue is soft. The stems tip over easily.

P = phosphorus

This nutrient is mainly required by flowering and fruit-bearing plants. If there is a lot of nitrogen available in the soil, insufficient phosphorus is absorbed.

  • Too little: The plants bloom and hardly or not at all fruit.
  • Optimal: rich floral flora as well as fruit set and fruit ripeness.
  • Too much: Stunted growth because important trace elements are not absorbed.

K = potassium

The nutrient potassium is related to the water balance of plants, it increases stability, frost resistance and resistance to sucking insects.

  • Too little: Growth inhibitions and wilting phenomena.
  • Optimal: The plant looks healthy and shows rapid and stable growth.
  • Too much: Growth retardation, leaf margin necrosis, root burns, leaf damage, stunted growth.

The meaning of NPK numbers in finished fertilizer products

So-called NPK fertilizers have different compositions; the figures indicate the nutrients they contain.

The figures on finished fertilizer products show the percentage of nitrogen, phosphorus and potassium. So you make a statement about how high the nutrients are dosed in the product. These figures can also be used to determine whether it is a nitrogen-based complete fertilizer (12 - 4 - 6) or a phosphorus-based complete fertilizer (11 - 14 - 17). This information is also important for the price comparison. A product with a higher concentration of nutrients is more expensive but does not need to be applied as frequently. The application rate g / m2 is also decisive for the price.

The right choice: nitrogen-based or phosphorus-based fertilizer?

Nitrogen fertilizer, so "green manure", is suitable for all plants, which should grow well and where the leaves are important. Examples: lawn, lettuce, cabbage or house plants such as palms, dieffenbachia and ferns.

Phosphorus fertilizer, So "bloom fertilizer" is suitable for all plants that should bloom and bear fruit. Examples: legumes, fruit trees, flower bulbs or house plants such as anthuriums, African violets and clive.

How useful are special fertilizers for certain groups of plants?

Large rose beds can be well supplied with a special rose fertilizer.

Special fertilizers for roses, lawns or rhododendrons are well matched to the individual plants. They are especially worthwhile if there are a large number of specific groups of plants in a garden. For the standard garden with many different plants, nitrogen and phosphorus fertilizers and lime are usually sufficient. These three products are great for getting through the gardening year.

Long-term fertilizers are applied once or twice a year. They prevent the soil from "washing out" quickly. Liquid foliar fertilizer is immediately absorbed through the leaves and the wood. This is useful for propelling, for example, fuchsias after hibernation.

How do I know if the dosage of mineral fertilizer is too high?

In the event of a significant overdose, plants will go limp a short time after application. The reason: Mineral fertilizer is in salt form, but salt draws water from the plant cells through the roots. This process is known as exosmosis. To save the plants, the only thing that helps is giving them plenty of water to reduce the salt content. However, the leaching of nutrients into the groundwater is the result. Therefore an exact calculation of the application rate is essential.

Fertilizer than Powder, liquid, pearl or granulate?

Fertilizers are offered in a wide variety of variants. But not every one is suitable for every plant.

  • Liquid: Liquid fertilizer is recommended for the weekly fertilization of plants in pots and tubs. The nutrients are soluble in water and are quickly absorbed by the plant, but unfortunately also quickly washed out of the soil into the groundwater.
  • Powder: Powdered organic fertilizer such as horn meal is quickly absorbed by microorganisms and made available to the plants. With horn shavings, it takes longer for the nutrients to be available. Powder is ideally suited for spreading with a spreader; a dust mask is recommended when spreading by hand.
  • Resin-coated: This form of fertilizer is always a slow release fertilizer that releases the nutrients slowly and evenly to its surroundings. Particularly suitable for plants in pots and tubs, but also for plants in the open. However, the products have a high price. The product names usually end in "cote".
  • Pearled / granulate: Perlated or granulated fertilizer is particularly suitable for beds in the open air. It is easy to learn how to apply the correct dosage by hand using the spreading method.

Warning: some fertilizers are poisonous

Some inorganic fertilizers can be toxic to animals such as dogs and cats. For this reason, organic fertilizers are recommended for pet owners.

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NDR 90.3 | The garden | 10/10/2019 | 8:00 p.m.