Table of contents:
- Feeding needs
- Top dressing after buying a plant and transplanting
- Which fertilizers are best?
- Ambulance when applying excessive doses of fertilizers
- Specialized fertilizers for different plant groups
- Factors affecting the absorption of fertilizers by plants
Ending. The beginning is in the article The role of macro- and microelements in plant nutrition.
For normal development, the plant needs to replenish the reserves of nutrients in time, which will be used to build new cells and maintain old ones.
Under natural conditions, the plant absorbs all the nutrients it needs from the soil, nature itself takes care of their replenishment. Soil is a single living organism. The animals inhabiting it and, especially, microorganisms with their vital activity constantly support its fertility. When growing plants in pot, we are not dealing with soil, but with soil, and often flower growers try in every possible way to eradicate any manifestation of life in it, be it earthworms or a soil fungus that has developed on the surface of the soil. Therefore, the function of fertilizing a plant should be taken over by a person, because any, even the most nutritious soil, quickly loses its nutritional value.
It is important to add all the substances necessary for plants, observing not only the dosage of individual components, but also strictly maintaining their proportions. In this case, it is necessary, first of all, to provide suitable conditions of detention, so that plants can fully assimilate the introduced substances. Often, bad conditions, which lead to physiological disturbances and diseases of plants, are attempted to be compensated for with enhanced fertilizing or treatments with stimulants, which can lead to the opposite effect and result in the death of the plant.
Peperomia blunt-leaved Variegata
The needs for feeding are determined by many factors: the type and age of the plant, the season, environmental conditions.
Special care should be taken when feeding newly sprouted seedlings - their needs are small, and feeding based on an adult plant will destroy them. In this case, it is better to refrain from fertilizing at all.
Actively growing specimens require the application of large doses of fertilizers, and older specimens that have stopped growing need them less. You can not feed plants immersed in a state of dormancy, undigested fertilizers will accumulate and saline the soil. For the same reason, diseased plants are not fed. Often the poor condition of the plant is associated with a disease of the root system, and the damaged roots are not able to absorb nutrients, an extra load at this moment only harms them.
Often indoor conditions are not optimal for plants, this reduces the growth rate, and, accordingly, their intake of nutrients. With a lack of light, too cool content, insufficient moisture supply, during the heat, the doses of fertilizers applied should be reduced.
The amount and composition of fertilizers applied should be specified for each plant individually, but there are some general rules for feeding indoor plants:
before a rest period, the dosage is gradually reduced, and after waking up, they begin to feed with small doses;
- before applying fertilizers, the substrate is pre-moistened so as not to cause burns to the roots;
- it is more useful to feed often, but in small doses, than rarely in high concentrations. It is most useful to divide the monthly rate by the approximate number of waterings per month and apply fractionally, one part with each watering;
- when acquiring a new fertilizer, use it at first in small doses to check the reaction of the plant;
- it is better to apply a little fertilizer than too much.
- for most flowering plants - phosphorus;
- for cacti - contain less nitrogen;
- for conifers - not rich in nitrogen and phosphorus;
- for orchids - they are of low concentration.
Top dressing after buying a plant and transplanting
Newly bought Dutch plants are usually well filled with long-lasting fertilizers (they can be seen as colored balls in the soil), which last for 3-6 months, which often equals a season of active growth. The composition of the ready-made soils used for transplantation also includes fertilizers designed for 1-2 months. Additional feeding during this period can cause an excess dosage and adversely affect the health of the plant, and sometimes even cause its death. Plants often show no signs of starvation throughout the year after purchase and do not require any additional feeding.
Which fertilizers are best?
By composition, the following groups of fertilizers are distinguished:
Mineral, which contain the nutrients necessary for the plant in the form of salts. These are the most easily assimilated fertilizers, for their absorption the plant does not need the presence of microorganisms, which is very important when growing plants in pots, where the normal microflora inherent in soils is disturbed. Depending on the composition of salts, mineral fertilizers can be simple, containing only one nutrient (nitrogen, phosphorus or potassium), and complex, containing several nutrients. The ratio of nutrients is prescribed on the package in the form of the NPK formula, where N is the nitrogen content, P is phosphorus, K is potassium. The magnesium content is often indicated - Mg. It is in them that indoor plants are especially needed. Plant sulfur is obtained in sufficient quantities from the soil or in the composition of the applied salts. Calcium deficiency usually does not occur either,it is sufficient in the irrigation water. The composition of good complex fertilizers necessarily includes a set of trace elements, which is also prescribed in the composition.
For various groups of plants, specialized mixtures have been developed that fully meet their needs, where all the main nutrients and trace elements are selected in such proportions that there is no imbalance in nutrition. When choosing mineral dressings, preference should be given to just such fertilizers. Strictly observe the application time and dosage of fertilizers so that the plant fully utilizes it, otherwise soil salinization will occur. Applying an increased dose of such fertilizers can quickly lead to plant death.
Organic- consist of substances of animal and plant origin, which plants are not immediately able to assimilate. They are prepared on the basis of manure, poultry droppings, peat. The process of decomposition of complex organic substances occurs under the influence of microflora, as a result, mineral substances available to plants are formed. Organic fertilizers exert their effect more slowly, and for their assimilation it is necessary to constantly maintain the microflora in the soil of the pot, for this there are special microbiological preparations. It is more difficult to overfeed the plant with organic fertilizer, however, it is impossible to accurately maintain the balance of the introduced nutrients, usually they have little potassium. When feeding potted plants with organic fertilizers, deviations from normal development sometimes occur, which are difficult to diagnose.The introduction of a large amount of organic matter can cause an outbreak of the development of individual microorganisms, which will lead to acidification and fermentation of the soil, and when irrigating with manure extracts, an unpleasant odor is inevitable.
In terms of the speed of action, only poultry manure is close to mineral fertilizers, but its use requires special care with dosages.
From personal experience. I have a cage with birds at home, I use the accumulating bird droppings for top dressing, occasionally scattering a small amount of it on the surface of the soil (a pinch per pot 1-2 times per season), continuing to feed with mineral complex fertilizers in the same mode. I do not observe any negative or visible positive influences.
Organo-mineral - humic fertilizers, consisting of organic matter and related mineral compounds. They are obtained by processing humic acids or materials containing them (peat, brown coal, silts, shale, humus) with weak alkalis, acids or salts. They contain humic compounds, nitrogen, phosphorus, potassium, magnesium and trace elements. Mineral nutrients form organo-mineral complexes with humic compounds, the mobility of nitrogen and potassium decreases, and phosphorus is converted into an easily assimilable form. This protects against exceeding the concentration of substances in the root zone and ensures prolonged action of the fertilizer. Some brands contain beneficial bacteria that aid in the absorption of the fertilizer.
Humates are salts of humic acids and preparations derived from them. Purified from ballast, containing a greater percentage of active nutrients, humates are more often called drugs or growth stimulants, and ballast ones produced without purification from impurities and the original substrate are called fertilizers. This division is due to differences in their methods of administration and dosage. The potassium and ammonium humates exhibit a growth-stimulating effect that significantly exceeds their immediate nutritional value.
Peat-based organo-mineral fertilizers are long-acting granular fertilizers (up to three years). Liquid forms of such fertilizers are also commercially available, they have one drawback - an alkaline reaction.
The dark color and liquid consistency of organic fertilizers gives unscrupulous entrepreneurs freedom of action, sometimes instead of fertilizers, something completely different appears in the bubbles. Be careful to always try a new brand of fertilizer on a small part of the plant and at low concentrations.
Inverse conical primrose
From personal experience. Having tried various combinations of fertilizing at home for many years, I settled on the use of complex mineral fertilizers with trace elements. Since there are a lot of plants, I have to prepare large volumes for dressing, so I buy dry mixes (brands Aquarin, Solution, etc., there are also more expensive imported counterparts). If there are few plants, then you can use liquid concentrates, in this case it is more convenient to measure small quantities. In most cases, universal fertilizers with approximately the same content of nitrogen, phosphorus and potassium are quite suitable. A wide range of mixtures with different ratios of nutrients for indoor plants, which allows you to take into account all the nuances of your needs, is represented by the Aquarin brand (Coniferous, Junior, Color, Tsvetochny, Super).
Adhering to the rule - better more often, but in smaller doses and better less than more - I dilute the fertilizer in a low concentration. Experience has shown that the use of those doses of fertilizers that are indicated in the instructions often leads to symptoms of an overdose, therefore I advise the initially recommended dose to be reduced by 2 times. If the instructions recommend adding 20 g of fertilizer to 10 liters of water and watering once a week, then I add 3-4 g (about 1/3 teaspoon) for 10 liters and water with this solution as often as the plant requires, but no the need to pre-wet the lump. The warmer and sunnier, the more active growth is and the more fertilizers are consumed by plants, the more often they require watering. Watering more often, I feed more. If it becomes cool and cloudy, then the growth rate decreases, the need for fertilizers also decreases,but it is also necessary to water less often at this time. I water less often - I feed less. Usually those plants that consume a lot of water (hibiscus, passionflower) turn out to be the most voracious, they have to be watered more often, and, accordingly, fed. Cacti and succulents require less watering, and, accordingly, they will receive less feeding. There are some species that require regular watering (ferns), but they are less in need of fertilizing, such I water alternately, with fertilizers and clean water.There are some species that require regular watering (ferns), but they are less in need of fertilizing, such I water alternately, with fertilizers and clean water.There are some species that require regular watering (ferns), but they are less in need of fertilizing, such I water alternately, with fertilizers and clean water.
Ambulance when applying excessive doses of fertilizers
Signs of an overdose are the plant's loss of turgor in a wet coma (the roots are not able to absorb water from concentrated solutions according to the law of osmosis), the appearance of withered spots, leaf fall. Remove the top layer of soil as soon as possible, pour plenty of water over the top of the pot and drain from the pallet. In this way, it will be possible to wash out a certain amount of fertilizer from the soil. Then carefully remove the lump from the pot, wrap it in paper towels or newspaper to remove excess moisture, leave to dry without the pot, and after drying, return it back to the pot and add fresh soil on top.
For different groups of plants, the ratio of nutrients in fertilizers will be different.
Specialized fertilizers for different plant groups
for decorative deciduous plants - rich in nitrogen;
There are exceptions. We repeat that hibiscus cannot be fed with fertilizers for flowering, large doses of phosphorus are harmful to them. Many plants originating from Australia, with poor phosphorus soils, also need to be adjusted for feeding, for them the use of fertilizers with a high phosphorus content is unacceptable.
Factors affecting the absorption of fertilizers by plants
It often happens that it seems that the fertilizer is chosen correctly, and the dosage is determined, but feeding is not beneficial. In addition to factors such as temperature and the amount of moisture, the acidity of the soil greatly affects the absorption of fertilizers.
The acidity of the soil affects the assimilation of the dressings introduced at the root… The optimum absorption of nutrients for most plants is in the range of slightly acidic or neutral values of acidity (hibiscus, citrus fruits, begonias, ferns). There are plants that prefer acidic soil (hydrangeas, gardenias, azaleas). others have adapted to live on alkaline soils (campanula, some hoyi, heliotrope). A deviation of the pH value to the acidic or alkaline side from the optimum for a given species leads to a deterioration in the absorption of nutrients by the roots, and even an increase in the doses of fertilizers will not increase their absorption. When planting and transplanting a plant, it is important to choose the right soil according to the degree of acidity. Almost all plants (excluding those preferring alkaline soils) should be watered with soft water, since calcium from hard water will gradually alkalize the soil.It is also necessary to pay attention to the pH of the applied fertilizers.
For an ambulance during fasting, it is more effective to use foliar feeding. This method of fertilizing will help with problems with soil acidity. In many plants, especially in epiphytic species, accustomed in nature to receive moisture and nutrients with atmospheric precipitation, leaves and stems absorb fertilizers well. Such dressings will be useful for species that cannot tolerate the accumulation of salts in the soil, as well as for plants that have sick or no roots. Prepare a weak solution of complex mineral fertilizer (its concentration is 5-10 times lower than indicated in the instructions, it is equal to 3-5 g / 10 l of water and corresponds to the concentration of salts of plant cell sap) and spray the leaves once a week.
Nutrients affect various life functions, often interacting closely with each other and exerting a joint influence on the same processes. Incorrect dosage will bring harm to plants instead of good, often interfering with the absorption of other nutrients. Do not exceed the dosage, select fertilizers for this type of plant, taking into account the stage of its development, use only complex fertilizers, which include the necessary macro- and microelements in the right proportions
Despite a large selection of ready-made fertilizer mixtures in retail chains, homemade dressings are still widely used. However, many of them are useless and even harmful to plants.
For an analysis of such methods of plant feeding, see the article Homemade fertilizers for indoor plants: benefit or harm?
Photo: Rita Brilliantova