Garden Fertilizer Analysis

Fertilization is a key agrotechnical measure aimed at providing plants with the necessary nutrients for their optimal growth, development, flowering, and fruiting. Nutrients are divided into macroelements/macronutrients (nitrogen, phosphorus, potassium - NPK; calcium, magnesium, sulfur - secondary macroelements/macronutrients) and microelements/micronutrients (iron, manganese, zinc, copper, boron, molybdenum, chlorine, nickel, cobalt). The choice of the right fertilizer depends on the type of plant, its growth stage, soil composition, and the season.

I. Organic Fertilizers

Organic fertilizers are of natural origin, improve soil structure, support the activity of soil microorganisms, and release nutrients gradually.

A. Farmyard Manure (livestock excrement)

Farmyard manure is a traditional and very valuable organic fertilizer. Its quality depends on the animal species, its diet, the bedding used, and the storage method. In most cases, it needs to be matured (composted) before use to prevent scorching plants and to destroy weed seeds and potential pathogens.

  1. Horse Manure: NPK (approx.): N: 0.5-0.7%, P2O5: 0.2-0.4%, K2O: 0.4-0.6%. May also contain Ca and Mg. Type: Warm manure (heating). Decomposes quickly and releases heat, which is beneficial for "hotbeds" and heavy, cold soils. Use: Ideal after ripening (at least 6-12 months). Incorporate into the soil in autumn or early spring. Suitable for nutrient-demanding vegetables (cucumbers, pumpkins, celery, cabbage), potatoes, fruit trees and shrubs, strawberries. Diluted fresh manure can be used to prepare liquid fertilizer (slurry).

  2. Cow Manure: NPK (approx.): N: 0.3-0.5%, P2O5: 0.15-0.25%, K2O: 0.4-0.6%. Also contains Ca and Mg. Type: Cold manure. Decomposes more slowly and heats less intensely. Use: More versatile than horse manure, suitable for most soils. Composting is ideal (6-12 months). Incorporate in autumn. Suitable for all types of vegetables, fruit trees, ornamental plants. Less concentrated, lower risk of scorching plants.

  3. Pig Manure: NPK (approx.): N: 0.4-0.6%, P2O5: 0.3-0.5%, K2O: 0.3-0.5%. Type: Cold and acidic manure. Use: Requires thorough composting (minimum 1 year), ideally with the addition of lime to neutralize acidity. Less suitable for direct fertilization due to the possible presence of pathogens and strong odor. After good maturation, suitable for fruiting vegetables and potatoes. Often used in biogas plants.

  4. Sheep Manure: NPK (approx.): N: 0.7-0.9%, P2O5: 0.4-0.6%, K2O: 0.8-1.0%. Richer in nutrients than cow or horse manure. Type: Warm manure, drier with higher dry matter content. Use: Needs to mature. Suitable for all soil types, especially for potassium-demanding plants (potatoes, tomatoes, vines). Apply cautiously due to higher nutrient concentration. Can be dried and granulated.

  5. Goat Manure: NPK (approx.): N: 0.6-0.8%, P2O5: 0.3-0.5%, K2O: 0.7-0.9%. Similar to sheep manure. Type: Warm manure. Use: Similar to sheep manure, needs to mature. Suitable for all soil types, especially for nutrient-demanding plants. Can be dried and granulated.

  6. Rabbit Manure: NPK (approx.): N: 1.5-2.4%, P2O5: 1.4-1.8%, K2O: 0.5-0.7%. One of the most concentrated farmyard manures. Also contains calcium. Type: Cold manure (although sometimes listed as mildly warm due to higher N content). Use: Can be used fresh (cautiously, especially with young plants) or composted. Excellent for vegetables, flowers, herbs. Its drier consistency and pellet form make it easy to handle. Can be used to prepare liquid fertilizer.

B. Poultry Manure

Poultry manure is a highly concentrated organic fertilizer, especially rich in nitrogen and phosphorus. It must be used carefully and diluted or well-composted to avoid scorching plants.

  1. Chicken Manure: NPK (approx.): N: 1.0-1.8%, P2O5: 1.5-2.0%, K2O: 0.8-1.0%. Significant calcium (Ca) and magnesium (Mg) content. Type: Very strong, "hot" type of fertilizer. Use: Always diluted (for fermentation - slurry) or well-composted (at least 6 months, ideally with other organic material). Granulated chicken manure is commonly available and safer to use. Suitable for fruiting vegetables, fruit trees, strawberries, and flowers during intensive growth.

  2. Turkey Manure: NPK (approx.): N: 1.2-1.7%, P2O5: 1.3-1.6%, K2O: 0.7-0.9%. Similar to chicken, may be slightly less concentrated. Contains calcium (Ca) and magnesium (Mg). Type: Strong, "hot". Use: Similar to chicken manure - diluted or composted. Suitable for nutrient-demanding plants.

  3. Duck and Goose Manure: NPK (approx.): N: 0.6-1.0%, P2O5: 0.5-1.4%, K2O: 0.4-0.6%. Less concentrated than chicken, wetter. Type: Cooler than chicken, but still relatively strong. Use: Better to compost. Suitable for various types of plants.

  4. Guineafowl Manure: NPK (approx.): Similar to chicken, may be slightly drier. N: ~1.5%, P2O5: ~1.8%, K2O: ~0.9%. Contains calcium (Ca) and magnesium (Mg). Type: Strong, "hot". Use: Like chicken manure - dilution or composting is essential.

  5. Quail Manure: NPK (approx.): N: 2.0-2.8%, P2O5: 1.5-2.0%, K2O: 0.8-1.0%. Very concentrated, comparable to or even stronger than rabbit manure. Contains calcium (Ca). Type: Very strong. Use: Thorough dilution or composting is absolutely essential. Very effective in small quantities.

  6. Pigeon Manure: NPK (approx.): N: 1.5-2.5% (can be up to 4%), P2O5: 1.0-2.0%, K2O: 0.8-1.2%. Very concentrated. Type: Very strong, "hot". Use: Use very carefully, well-diluted (slurry) or long-term composted. Traditionally valued for its strength.

C. Guano

Guano is the excrement of seabirds or bats. It is a highly concentrated organic fertilizer.

  1. Bird Guano (seabird): NPK (approx.): N: 10-16%, P2O5: 8-12%, K2O: 2-3%. Also rich in micronutrients. Type: Very strong, fast-acting. Use: Used in small doses, dissolved in water or carefully incorporated into the soil. Suitable for all plants, especially during growth and flowering.

  2. Bat Guano: NPK (approx.): Variable depending on the bats' diet. Insectivorous bat guano has higher nitrogen (N) content (e.g., N: 10%, P2O5 3%, K2O: 1%). Fruit-eating bat guano has higher phosphorus (P) content. Type: Strong, containing enzymes and microorganisms beneficial to the soil. Use: Similar to bird guano, in small doses. Suitable for promoting root growth and flowering.

D. Composts

Composting is a controlled process of decomposition of organic materials by microorganisms. The resulting product - compost - is an excellent fertilizer and soil conditioner.

  1. Homemade Compost: NPK (approx.): Highly variable, depends on the input materials. Typically N: 0.5-1.5%, P2O5: 0.2-0.8%, K2O: 0.5-1.0%. Contains a wide range of micronutrients and organic matter. Type: Universal, balanced fertilizer and soil conditioner. Use: Matured compost is incorporated into the soil in spring or autumn, used for planting, for supplementary fertilization during vegetation, as part of substrates. Improves soil structure, water retention, and aeration.

  2. Commercial Compost: NPK (approx.): Declared by the manufacturer, often standardized. Can be enriched with additional nutrients. Type: Depends on the manufacturer and raw materials used (e.g., green compost, compost from sewage sludge - which is subject to strict standards). Use: Similar to homemade compost. When choosing, check the composition and certification.

  3. Vermicompost (worm compost): NPK (approx.): N: 1.0-2.0%, P2O5: 0.5-1.5%, K2O: 0.5-1.0%. Very rich in enzymes, growth hormones (auxins, cytokinins, gibberellins), humic acids, and beneficial microorganisms. Type: High-quality, biologically active fertilizer. Use: Excellent for seedling pre-growing, mixing into substrates, fertilizing houseplants and balcony plants, vegetables. Even a small amount has a significant positive effect.

  4. Worm Tea (vermicompost leachate): NPK (approx.): Lower concentrations than in solid vermicompost, but contains soluble nutrients, enzymes, and beneficial microorganisms. Type: Liquid, biologically active fertilizer and stimulant. Use: Dilute with water (typically 1:5 to 1:10) and use for watering or as a foliar spray. Promotes plant growth and resistance.

E. Green Manure

Green manure is the practice of growing certain plants with the aim of later incorporating them into the soil to enrich it with organic matter and nutrients.

Plants for green manure:

  • Phacelia tanacetifolia: NPK is not directly measurable as a fertilizer, but it binds atmospheric nitrogen (less than legumes), suppresses weeds and nematodes. Grows quickly.
  • Lupine: Leguminous plant, significantly binds atmospheric nitrogen (N). Improves soil structure.
  • Clover (e.g., crimson clover): Leguminous, binds atmospheric nitrogen (N).
  • Peas, Vetch: Leguminous, bind atmospheric nitrogen (N).
  • Rapeseed, White Mustard: Brassicaceae, quickly produce a lot of green mass, have a phytosanitary effect (suppress some diseases and pests, e.g., nematodes). Mustard binds available nutrients and prevents their leaching.

Benefits: Addition of organic matter, improved soil structure, aeration, erosion protection, weed suppression, nitrogen enrichment (especially legumes), support for soil life. Use: Plants are allowed to grow to a certain stage (usually before flowering or at the beginning of flowering) and then cut and incorporated into the soil.

F. Plant Residues and Materials

  1. Straw: NPK (approx.): Low content (N: ~0.5%, P2O5: ~0.2%, K2O: ~1.0%). The main benefit is organic matter. Use: As mulch (note, it consumes nitrogen from the soil during decomposition, it is advisable to add nitrogen fertilizer), part of compost (provides carbon), bedding for animals. Incorporated into the soil, it decomposes slowly.

  2. Leaves: NPK (approx.): Variable depending on the tree species (N: 0.5-1.0%, P2O5: 0.1-0.2%, K2O: 0.3-0.8%). Oak and beech leaves are more acidic and decompose more slowly. Use: Ideal for composting (leaf mold - quality humus), as mulch (especially for acid-loving plants, if from acidic trees).

  3. Grass (mown grass): NPK (approx.): N: 0.8-1.5%, P2O5: 0.2-0.5%, K2O: 0.8-1.5% (fresh). Use: In a thin layer as mulch (a thick layer can steam, rot, and cause chlorosis), an excellent compost additive (rich in nitrogen), for preparing liquid fertilizer (grass slurry).

  4. Wood Chips/Raw Bark: NPK (approx.): Very low nutrient content. High carbon (C) content. Use: Mainly as mulch (long-term, suppresses weeds, retains moisture). During decomposition in the soil, it draws nitrogen, so it is advisable to add nitrogen fertilizer when incorporating it. Raw chips are not a direct fertilizer.

  5. Composted Wood Chips/Bark: NPK (approx.): Still relatively low nutrient content, but the composting process stabilizes the C:N ratio and adds a certain amount of available nutrients and humus. Use: As quality mulch, part of substrates for acid-loving plants (e.g., blueberries, rhododendrons - if from conifers), for improving the structure of heavy soils.

  6. Coffee Grounds: NPK (approx.): N: ~2.0%, P2O5: ~0.3%, K2O: ~0.3%. Also contains magnesium, copper, and other micronutrients. Slightly acidic reaction. Use: In small amounts directly into the soil (especially for acid-loving plants like blueberries, azaleas, rhododendrons, hydrangeas), an excellent compost additive (activator), for repelling slugs and some types of ants.

  7. Wood Ash (from clean, chemically untreated wood): NPK (approx.): N: almost none, P2O5: 1-3%, K2O: 5-10% (sometimes more, depending on wood type). Significant calcium (Ca: 20-35%), magnesium (Mg) and micronutrient content. Alkaline reaction (increases soil pH). Use: Cautiously, in small doses in autumn or early spring. Suitable for soils with potassium and calcium deficiencies, for plants preferring neutral to alkaline soil (most vegetables, fruit trees). Unsuitable for acid-loving plants and for soils with high pH. Do not use ash from coal or varnished/impregnated wood.

  8. Peat: NPK (approx.): Very low nutrient content. Properties: High water retention capacity, improves the structure of both light and heavy soils. Acidic reaction (light peat pH 2.5-4.5, dark peat can be less acidic). Use: Mainly as part of substrates to improve physical properties, to adjust pH for acid-loving plants. Not primarily a fertilizer. Ecological peat extraction is controversial, alternatives are sought (e.g., coir).

G. Other Organic Fertilizers (often commercially available in processed form)

  1. Bone Meal: NPK (approx.): N: 1-6% (often around 3-4%), P2O5: 15-25% (main component), K2O: negligible. Rich in calcium (Ca). Type: Slow-release fertilizer, mainly a source of phosphorus. Use: When planting bulbs, perennials, fruit trees, and shrubs to promote root and flower formation. Incorporated into the soil. Acts long-term.

  2. Blood Meal: NPK (approx.): N: 12-14%, P2O5 1-2%, K2O: <1%. Type: Fast-acting nitrogen fertilizer. Use: For rapid nitrogen replenishment, especially in spring or for plants with high nitrogen requirements (leafy vegetables). Use with caution, can scorch plants. May repel some animals (e.g., rabbits).

  3. Horn Meal (horn meal, horn shavings): NPK (approx.): N: 10-14%, P2O5: <1%, K2O: <1%. Also contains Ca. Type: Slow and long-term release nitrogen fertilizer. Use: Universal use for vegetables, fruit trees, ornamental plants. Incorporated into the soil. Safe, does not scorch plants.

  4. Fish Emulsion/Meal: NPK (approx.): Emulsion: N: 2-5%, P2O5 1-4%, K2O: 0.5-2%. Meal: N: 8-10%, P2O5: 4-6%, K2O: 1-2%. Also contains micronutrients and amino acids. Type: Relatively fast-acting, complex organic fertilizer. Use: Emulsion is diluted with water and used for watering or foliar application. Meal is incorporated into the soil. Suitable for all types of plants. Has a characteristic odor.

  5. Feather Meal: NPK (approx.): N: 12-15%, P2O5: <1%, K2O: <1%. Type: Very slow-release nitrogen fertilizer. Use: As a long-term source of nitrogen, similar to horn meal. Incorporated into the soil.

  6. Leather Meal: NPK (approx.): N: 5-10%. Nitrogen release depends on processing (e.g., chrome-tanned leather decomposes very slowly and may contain chromium). Type: Slow-release nitrogen fertilizer. Use: Less common in consumer packaging. It is important to pay attention to the origin and processing due to potential contaminants.

  7. Molasses: NPK (approx.): Low NPK content (e.g., N: ~1%, P2O5: ~0.1%, K: ~5-7%). The main benefit is carbohydrates, potassium, and micronutrients. Type: Stimulant for soil microorganisms, source of potassium. Use: Dilute with water and use for watering. Promotes microbial activity in the soil, which improves nutrient release. Often part of commercial bio-fertilizers.

  8. Plant Extracts (e.g., nettle slurry, comfrey slurry): Nettle Slurry: NPK (approx.): N: 0.5-1.0%, P2O5: 0.1-0.3%, K2O: 0.8-1.2%. Rich in iron (Fe), magnesium (Mg), calcium (Ca). Comfrey Slurry: Rich mainly in potassium (K) and calcium (Ca), phosphorus (P). Type: Liquid fertilizer and biostimulant. Use: Diluted with water (typically 1:10 to 1:20) for watering or as a foliar spray (can also act against some pests, e.g., aphids). Prepared by fermenting plants in water.

  9. Seaweed Extract (Ascophyllum nodosum and others): NPK (approx.): Low NPK content (e.g., N: ~1%, P2O5: ~0.2%, K2O: ~2-3%). The main benefit is micronutrients (iodine, boron, manganese, zinc), amino acids, vitamins, and growth hormones (cytokinins, auxins, gibberellins). Type: Biostimulant and supplementary fertilizer. Use: Dilute with water and apply to leaves or soil. Promotes germination, rooting, growth, flowering, stress resistance.

  10. Cocoa Hulls (cocoa mulch): NPK (approx.): N: 2.5-3.0%, P2O5: 1.0-1.5%, K2O: 2.5-3.0%. Type: Organic mulch with nutrient content. Use: As a decorative and nutritious mulch. Retains moisture, suppresses weeds, gradually releases nutrients. Caution: Contains theobromine, which is toxic to dogs.

  11. Mushroom Substrates (used, e.g., after growing oyster mushrooms, button mushrooms): NPK (approx.): Variable, but usually N: 1-2%, P2O5: 0.5-1.5%, K2O: 1-2%. Contains organic matter and mycelial residues. Type: Soil conditioner and slow-acting fertilizer. Use: After composting (to prevent possible diseases), incorporated into the soil to improve structure and provide nutrients. Suitable for vegetables and flowers.

H. Insect Frass Fertilizer

Insect frass, often referred to by the English term "frass", is the product of insect digestion from farmed insects (most commonly mealworm larvae - Tenebrio molitor, or black soldier fly larvae - Hermetia illucens). It is a mixture of insect excrement and residual feed.

NPK (approx.): NPK values may vary depending on the insect species and its diet, but typically range from: N: 2-5%, P2O5: 1-4%, K2O: 1-3%. Other significant components: Chitin: A significant component found in the insect exoskeleton and its residues in the frass. Chitin can stimulate plant defense mechanisms against pests and diseases in the soil. It promotes the growth of beneficial microorganisms that break down chitin, thereby suppressing pathogenic fungi and nematodes. Type: Dry fertilizer, usually available as a fine powder or small granules. It is practically odorless. Use as dry fertilizer: Suitable for a wide range of plants including vegetables, fruits, flowers, herbs, and houseplants. Incorporate into the soil before sowing or planting. Use as liquid fertilizer ("Frass tea"): Similar to vermicompost tea, a leachate can also be prepared from insect frass for watering or foliar application. Simply mix in water and let it steep (or aerate). Usually does not cause plant scorching if used according to recommendations.

II. Mineral Fertilizers (Industrial Fertilizers)

Mineral fertilizers contain nutrients in an inorganic form, are usually rapidly soluble, and readily available to plants. Their advantage is high nutrient concentration and precisely defined composition. However, incorrect use can damage plants, salinize the soil, or pollute water sources.

A. Nitrogen (N) Fertilizers

  1. Ammonium Nitrate: NH4NO3 N content: Typically 33-34.5% N (half in ammonium form NH4+, half in nitrate form NO3-). Use: Universal nitrogen fertilizer, both fast and slow-acting. Suitable for both basic fertilization and supplementary fertilization during vegetation. Slightly acidifies the soil. Use with caution due to possible explosiveness (hence often with additives).

  2. Urea: CO(NH2)2 N content: 45-46% N (in amide form). Use: Most concentrated nitrogen fertilizer. In the soil, it enzymatically converts to ammonia and then to nitrates. Suitable for basic fertilization and foliar application (in low concentrations). Acts slower than nitrates.

  3. Ammonium Sulfate: (NH4)2SO4 N content: Approx. 21% N (in ammonium form NH4+). S content: Approx. 24% S. Use: Suitable for sulfur-demanding plants (brassicas, onions, legumes) and for acid-loving plants (e.g., blueberries, rhododendrons), as it physiologically acidifies the soil. Nitrogen is released more slowly.

  4. Calcium Nitrate: Ca(NO3)2 N content: Approx. 15.5% N (in nitrate form NO3-). Ca content: Approx. 19% Ca (26.5% CaO). Use: Fast-acting nitrogen fertilizer, also provides calcium. Suitable for supplementary fertilization during vegetation, especially for fruiting vegetables (prevention of blossom end rot caused by calcium deficiency). Slightly alkaline reaction.

  5. Sodium Nitrate (Chile Saltpeter): NaNO3 N content: Approx. 16% N (in nitrate form NO3-). Also contains sodium (Na). Use: Fast-acting. Suitable for sodium-tolerant plants (e.g., beets). Physiologically alkaline. Used less frequently.

B. Phosphorus (P) Fertilizers

  1. Single Superphosphate (SSP): Ca(H2PO4)2+CaSO4 P2O5 content: 16-20% (water-soluble phosphorus). Also contains sulfur (S) and calcium (Ca). Use: For basic fertilization in autumn or spring. Acts slower. Slightly acidifies the soil.

  2. Triple Superphosphate (TSP): Ca(H2PO4)2 P2O5 content: 44-48% (water-soluble phosphorus). Does not contain sulfur. Use: More concentrated than single superphosphate, for basic fertilization.

  3. Diammonium Phosphate (DAP): (NH4)2HPO4 N content: Approx. 18%. P2O5 content: Approx. 46%. Use: Concentrated fertilizer containing nitrogen and phosphorus. Suitable for basic fertilization. Temporarily increases pH around granules after application to soil.

  4. Monoammonium Phosphate (MAP): NH4H2PO4 N content: Approx. 11%. P2O5 content: Approx. 52%. Use: Concentrated fertilizer with high phosphorus content and lower nitrogen content. Suitable for starter fertilization, promotes root development. Slightly acidifies the soil.

C. Potassium (K) Fertilizers

  1. Potassium Chloride (Muriate of Potash): KCl K2O content: 50-60%. Contains chlorine (Cl). Use: Most common potassium fertilizer. Suitable for basic autumn fertilization (chlorine partially leaches out by spring). Some plants are sensitive to chlorine (e.g., potatoes, onions, cucumbers, fruit trees, vines - for these, potassium sulfate is more suitable).

  2. Potassium Sulfate: K2SO4 K2O content: 48-52%. S content: Approx. 18% S. Use: Suitable for chlorine-sensitive plants and for sulfur-demanding plants. Can be used throughout the growing season. Slightly acidifies the soil.

  3. Potassium Nitrate (Saltpeter): KNO3 N content: Approx. 13% (in nitrate form).

D. Calcium (Ca) Fertilizers

  1. Calcium Cyanamide: CaCN2 N content: Approx. 19% (in cyanamide form). Ca content: Approx. 50% CaO. Use: Acts slowly. Has herbicidal, fungicidal, and insecticidal effects (disinfects the soil). Apply 2-3 weeks before sowing/planting. Suitable for autumn or early spring fertilization.

  2. Ground Limestone (Calcium Carbonate): CaCO3 Ca content: Approx. 30-40% Ca (50-70% CaO). May also contain Mg. Use: For liming acidic soils, improving soil structure, and nutrient availability. Acts long-term. Apply in autumn.

  3. Hydrated Lime (Slaked Lime): Ca(OH)2 Ca content: Approx. 45-50% Ca (60-70% CaO). Use: Fast-acting for pH adjustment. Apply cautiously, can "scorch" plants. Not suitable for regular fertilization.

  4. Calcium Sulfate (Gypsum): CaSO4·2H2O Ca content: Approx. 23% Ca (32% CaO). S content: Approx. 18% S. Use: Provides calcium and sulfur without significant soil pH change. Suitable for improving the structure of saline and heavy clay soils.

E. Magnesium (Mg) Fertilizers

  1. Magnesium Sulfate (Epsom Salt): MgSO4·7H2O Mg content: Approx. 10% Mg (16% MgO). S content: Approx. 13% S. Use: Fast-acting fertilizer for correcting magnesium deficiency. Apply by watering or foliar spray. Suitable for conifers (against browning), vegetables, fruit trees.

  2. Kieserite (Magnesium Sulfate Monohydrate): MgSO4·H2O Mg content: Approx. 15-17% Mg (25-28% MgO). S content: Approx. 20-22% S. Use: Slower dissolving than Epsom salt, suitable for basic fertilization.

  3. Dolomite: (see Calcium Fertilizers) - source of Mg and Ca

F. Sulfur (S) Fertilizers

Sulfur is important for protein and enzyme formation.

  1. Elemental Sulfur: S S content: Approx. 90-99% S. Use: For lowering soil pH for acid-loving plants (e.g., blueberries, rhododendrons). Acts slowly.

  2. Ammonium Sulfate: (see Nitrogen Fertilizers)

  3. Potassium Sulfate: (see Potassium Fertilizers)

  4. Magnesium Sulfate: (see Magnesium Fertilizers)

G. Complex (Multi-Component) Mineral Fertilizers

Contain combinations of several macroelements and often micronutrients.

  1. NPK Fertilizers: Contain nitrogen (N), phosphorus (P), and potassium (K) in various ratios (e.g., 15-15-15, 8-16-24). Use: Wide range, depending on nutrient ratio for basic fertilization and supplementary fertilization.

  2. NP, NK, PK Fertilizers: Contain only two of the main nutrients (e.g., DAP and MAP are NP fertilizers, potassium nitrate is an NK fertilizer).

  3. Complete Fertilizers: Contain N, P, K, and often secondary elements (Ca, Mg, S) and micronutrients. Provide more comprehensive nutrition.

  4. Specialized Blends: Formulated for specific plants (e.g., fertilizer for conifers - often with higher Mg content; for fruiting vegetables - with higher K content; for ornamental shrubs, for lawns, for orchids, etc.) or growth stages (e.g., starter fertilizer, flowering fertilizer).

  5. Slow/Controlled-Release Fertilizers: Mineral granules with a coating (e.g., polymer, sulfur) that regulates nutrient release over a long period (e.g., 3, 6, 9, 12 months). Examples: Osmocote, Plantacote. Use: For planting, in substrates for potted plants, for lawns. Reduce the risk of over-fertilization and nutrient loss through leaching.

  6. Glass Fertilizers (Frits, Vitreous fertilizers): Glass fertilizers are inorganic compounds of nutrients (macro and micronutrients such as P, K, Ca, Mg, B, Fe, Mn, Zn, Cu, Mo) fused into a glassy matrix (frits). Nutrients are released from the glassy matrix very slowly, by gradual dissolution of the glass due to soil moisture and weak organic acids produced by plant roots and soil microorganisms. Use: Long-term reserve fertilization when establishing permanent crops (orchards, vineyards, ornamental trees, forest nurseries). For substrates for plants with a long growing season.

  7. Water-Soluble Fertilizers: Crystalline mixtures designed for dissolving in water for watering or foliar application. Allow rapid nutrient supply. Examples: Kristalon product line (various formulations for different plants and growth stages – e.g., Kristalon Start, Flower and Fruit, Autumn), Wuxal Super/Wuxal Calcium (often containing micronutrients and biostimulants).

H. Popular Blends (examples for the Slovak/Czech market):

  • Cererit (e.g., Cererit Original, Cererit Gold): Universal granulated NPK fertilizer with micronutrients.
  • Forestina: Wide range of fertilizers for various plants (ornamental, vegetables, fruits).
  • Agro (Agro CS): Comprehensive range of fertilizers, including specialized ones (e.g., for blueberries, roses).
  • Kristalon: Water-soluble fertilizers for different growth stages and plant types.
  • Hortus: Fertilizers for specific crops and applications.
  • Liquid NPK fertilizers: Fast-acting for houseplants and balcony plants (e.g., Florovít).
  • Substrates with fertilizer: Pre-prepared substrates with added controlled-release fertilizer (e.g., Agro Substrates).

III. Micronutrient Fertilizers

Micronutrients are as important for plants as macronutrients, although they are only needed in very small quantities. However, their deficiency can cause serious growth and development disorders.

A. Types of Micronutrient Fertilizers

  1. Single-Component Micronutrient Fertilizers: Contain only one micronutrient (e.g., ferrous sulfate, zinc sulfate, borax). Use: For addressing specific deficiencies (e.g., chlorosis from iron deficiency).

  2. Multi-Component Micronutrient Fertilizers (Micronutrient Complexes): Contain a mixture of several micronutrients. Use: For preventive micronutrient supply or in cases of complex deficiencies.

  3. Chelated Micronutrient Fertilizers: Chelates are organic compounds that "coat" metal ions (Fe, Mn, Zn, Cu) and protect them from precipitation in the soil, thereby increasing their availability to plants, especially in alkaline and calcareous soils. Examples: Fe-EDTA, Mn-EDTA, Zn-EDTA, Cu-EDTA. Use: Very effective for foliar application and in hydroponic systems.

B. Common Micronutrients and Their Deficiencies

  1. Iron (Fe): Deficiency: Chlorosis (yellowing) of young leaves with prominent green venation. Solution: Iron-containing fertilizers (e.g., ferrous sulfate, iron chelate Fe-EDTA).

  2. Manganese (Mn): Deficiency: Similar to iron, yellowing between veins on younger leaves. Solution: Manganese sulfate, manganese chelate.

  3. Zinc (Zn): Deficiency: Small, deformed leaves, shortened internodes. Solution: Zinc sulfate, zinc chelate.

  4. Copper (Cu): Deficiency: Dieback of terminal buds, pale leaves. Solution: Copper sulfate, copper chelate.

  5. Boron (B): Deficiency: Deformations, cracking of fruits and stems, dieback of growth tips. Solution: Borax, boric acid.

  6. Molybdenum (Mo): Deficiency: Yellowing, paling of leaves, especially in brassicas ("whiptail"). Solution: Ammonium/sodium molybdate.

C. Application of Micronutrient Fertilizers

  1. Foliar Application: The most common and effective method, especially for chelated forms. Nutrients are rapidly absorbed by leaves.

  2. Soil Application: Less effective for some micronutrients (e.g., Fe) due to their immobilization in the soil. Suitable for a wider range of micronutrient fertilizers.

  3. Hydroponics: Precise dosing of micronutrients is crucial in hydroponic systems.

IV. Foliar Fertilizers

Foliar fertilizers are nutrient solutions applied directly to plant leaves. They serve for rapid nutrient replenishment, deficiency correction, or as supplementary nutrition.

A. Composition of Foliar Fertilizers

  1. Macronutrients (N, P, K): Fertilizer solutions containing one or more macronutrients (e.g., urea solution (N), potassium nitrate solution (N, K)). Used for rapid supply of these basic nutrients.

  2. Secondary Macronutrients (Ca, Mg, S): Fertilizers containing calcium (e.g., calcium nitrate solution, calcium chloride), magnesium (e.g., magnesium sulfate solution – Epsom salt), or sulfur. Important for specific plant needs (e.g., Ca against blossom end rot, Mg against browning of conifers).

  3. Micronutrients (Fe, Mn, Zn, Cu, B, Mo, Cl, Ni, Co): Fertilizers containing one or more micronutrients, often in chelated form for better availability (e.g., Fe-EDTA, Mn-EDTA). Used to address specific micronutrient deficiencies that manifest as various symptoms (chlorosis, leaf deformations, etc.).

B. Types of Foliar Fertilizers

  1. Universal Foliar Fertilizers: Contain a balanced ratio of essential macronutrients (N, P, K) and often a mix of micronutrients. Suitable for a wide range of plants for general growth and vitality support.

  2. Specialized Foliar Fertilizers: Formulated for specific plant species (e.g., for cereals, vines, fruit trees, vegetables) or for specific goals (e.g., promoting flowering, increasing stress resistance).

  3. Foliar Fertilizers with High Micronutrient Content: Aimed at providing a complex of micronutrients. Often used preventively or when a deficiency of several micronutrients is detected. Example: Mikromax - micronutrients in chelated form.

  4. Foliar Fertilizers with Added Biostimulants: In addition to nutrients, they also contain substances such as amino acids, humic acids, seaweed extracts, vitamins, which support plant metabolism and nutrient uptake.

C. Advantages and Disadvantages of Foliar Fertilizers

Advantages:

  • Rapid nutrient absorption by leaves.
  • Possibility of rapid deficiency correction.
  • More efficient nutrient utilization in some cases (e.g., with unfavorable soil pH, drought).
  • Lower nutrient losses due to leaching.

Disadvantages:

  • Not a substitute for basic soil fertilization.
  • Risk of scorching leaves at too high concentrations.
  • Limited plant capacity for nutrient uptake through leaves (larger doses must be applied to the soil).
  • Requires special applicators (sprayers).

D. Important Tips for Foliar Fertilization

  • Apply at the right time: Ideally in the morning or evening when it is cooler and the leaves are damp (but not wet), to minimize evaporation and leaf scorching.
  • Adhere to recommended concentrations.
  • Use a sprayer with a fine mist.

V. Conclusion and Practical Tips

Choosing and correctly using fertilizers is crucial for the health and productivity of your garden. It is important to understand that there is no universal "best" fertilizer, but it is always necessary to consider the specific needs of plants and soil properties.

Practical Tips:

  1. Soil Test: The best way to determine the current nutrient status and pH of the soil. Helps in selecting the right fertilizer and its dosage.
  2. Organic vs. Mineral: Organic fertilizers improve soil structure and long-term fertility. Mineral fertilizers provide a fast and precise supply of nutrients. A combination of both is ideal.
  3. Plant Type and Growth Stage: Different plants have different requirements. Vegetables need different nutrients during growth, flowering, and fruit trees after harvest.
  4. Dosage and Frequency: Adhere to the manufacturer's recommended dosage. Less is often more. Excessive fertilization can damage plants.
  5. Integrated Approach: Combine organic and mineral fertilization, consider green manure, composting, and other practices to maintain long-term soil fertility.
  6. Observe Plants: Monitor plants for symptoms of nutrient deficiency or excess.
  7. Environmental Consideration: Avoid excessive fertilization, which can lead to water and soil pollution.

Something about miraculous products (anti-scam paragraph) Lately, miraculous products (not just for quick weight loss or penis enlargement) that are supposed to ensure you a fabulous harvest are popping up like mushrooms after rain. With common sense...