Fertilizer sections at nurseries, garden centers, and supply stores dazzle the gardener. The shelves are piled with boxes and bottles, the floors covered with bags stacked high. Labels identify the package contents as organic compost, rose food or vegetable food, lawn fertilizer or general-purpose fertilizer. In some stores, you’ll find bins filled with bone meal, blood meal, or hoof-and-horn meal―all labeled natural fertilizer. Choosing the right products to keep your plants healthy can often be a bit confusing.
Regardless of its type, any fertilizer you buy will come with information about the nutrients it contains, so you want to understand the N-P-K-ratio.
Prominently featured, the N-P-K-ratio is the percentage the product contains by volume of nitrogen (chemical symbol N), phosphorus (P), and potassium (K). A 16-16-16 fertilizer, for example, contains 16% nitrogen, 16% phosphorus, and 16% potassium. A 25-4-2 formulation contains 25% nitrogen, 4% phosphorus, and 2% potassium.
All fertilizers contain at least one of these components; if any is missing, the ratio will show a zero for that nutrient. (A 12-0-0 fertilizer contains nitrogen but no phosphorus or potassium, for instance).
Boxed, bagged, and bottled products display the N-P-K ratio on the label. For fertilizers sold in bulk from self-serve bins, the ratio is noted on the bin. One tip: Be sure to write the information on the bags you fill before you bring them home.
Complete and Incomplete Fertilizers
A fertilizer containing all three major nutrients is called a complete fertilizer; a product that supplies only one or two of them is an incomplete fertilizer.
Using a complete fertilizer for every garden purpose seems sensible, but, in fact, it isn’t always the best choice. If the soil contains sufficient phosphorus and potassium and is deficient only in nitrogen (as is often the case), you can save money by using an incomplete fertilizer that provides nitrogen alone (ammonium sulfate, for example). In some instances, complete fertilizers can even harm a plant. Exotic, bright-blossomed proteas, for example, will not tolerate excess phosphorus: they “glut” themselves on it and then die.
The inexpensive soil test kits sold at garden centers can give you a rough idea of the nutrients available in various parts of your garden. For a more detailed evaluation, you may want to pay for professional analysis, and there are mail-in versions of soil test kits, too. By revealing which nutrients may be lacking, testing can help you choose an appropriate fertilizer.
General and Special-Purpose Fertilizers
The various products labeled “general-purpose fertilizers” contain either equal amounts of each major nutrient (N-P-K ratio 12-12-12, for example) or a slightly higher percentage of nitrogen than of phosphorus and potassium (such as a 12-8-6 product). Such fertilizers are intended to meet most plants’ general requirements throughout the growing season.
Special-purpose fertilizers, on the other hand, are formulated for specific needs. They’re aimed at the gardener who wants a particular combination of nitrogen, phosphorus, and potassium for certain plants or garden situations. These fertilizers are of three general types.
One type, used during the period of active growth, contains largely nitrogen. Such products, with N-P-K ratios such as 16-6-4, are often used in spring, when you want to encourage lush growth or green up your lawn.
Another type is meant to stimulate root growth, stem vigor, and flower and fruit production. Fertilizers of this sort contain little nitrogen and higher levels of phosphorus and potassium; the N-P-K ratio may be 3-20-20, for example. These products are applied at different times and in different ways, depending on what you want to achieve. When you prepare a new planting area, for instance, you’ll work a dry granular fertilizer of this sort deeply into the soil, putting the phosphorus and potassium where roots can absorb them. The nutrients help strengthen the new plants’ developing stems and encourage the growth of a dense network of roots.
To promote flower production and increase the yields of fruit or vegetable crops, you apply the same sort of fertilizer to established plants after they’ve completed their first flush of growth. You can use either dry granules, scratching them lightly into the soil, or apply a liquid formula with a watering can or a hose-end applicator.
A third group of fertilizers is designed for use on specific plants. These feature the N-P-K ratios determined to elicit the best performance from the particular plant, as well as other elements proven valuable to that plant. Such fertilizers are named according to the plant they’re intended to nourish. Especially useful are formulas for citrus trees and acid-loving plants such as camellia and rhododendron.
Recently, other such plant-specific fertilizers have appeared on nursery shelves, each claiming to be the best choice for a certain plant or group of plants; you may see several sorts of “tomato food” or “flower fertilizer,” for example. The jury is still out on the benefit of many of these products, and you will often do just as well to use a general-purpose type. The main distinction is often the price: the “special” formulas are usually costlier than general-purpose kinds.
Organic Fertilizers
Organic fertilizers are derived from the remains of living organisms; blood meal, bone meal, cottonseed meal, and fish emulsion are just a few of the many available types. Organic fertilizers release their nutrients slowly: rather than dissolving in water, they’re broken down by bacteria in the soil, providing nutrients as they decompose.
One of the many benefits of organics is they improve the “structure” of the soil the microorganisms that convert nutrients so plants can access them. Micronutrients are also often present, but they are not in synthetics.
Because these fertilizers act slowly, it’s almost impossible to “burn” or kill lawns or plants by applying too much (overdosing with synthetics, in contrast, can have potentially fatal results). Some manufacturers combine a variety of organic products in one package, then offer them for general-purpose or specialized use. Finally, they aren’t as water-soluble as synthetics, which means they won’t leach into waterways.
Two commonly used soil amendments―compost and manure―have some nutritive value and can be used as part of an organic fertilizing program. The N-P-K ratio of compost varies from 1.5-.5-1 to 3.5-1-2. Chicken manure’s N-P-K ratio ranges from 3-2.5-1.5 to 6-4-3; that of steer manure is usually a little less than 1-1-1.
Fertilizers containing seaweed are gaining favor with many gardeners. Besides providing nutrients in a form immediately available to plants, seaweed contains mannitol, a compound that enhances absorption of nutrients already in the soil, and various hormones that stimulate plant growth. And the carbohydrates in seaweed break down rapidly, nourishing soil-dwelling bacteria that fix nitrogen and make it available to plant roots.
Mixed with water and sprayed directly on foliage, seaweed-containing fertilizers can have dramatic effects in a matter of days. Plants green up and begin to produce new growth, and those that are weak stemmed and straggly straighten up and become stronger.
Synthetic fertilizers
These products are derived from the chemical sources listed on the product label. They’re faster acting than organic kinds and provide nutrients to plants quickly, making them a good choice for aiding plants in severe distress from nutrient deficiencies, but they are more likely to “burn” the plant.
Synthetic fertilizers are sold both as dry granules to be applied to the soil and as dry or liquid concentrates to be diluted in water before application. In dry form, they’re usually less expensive than their organic counterparts. In some of the dry granular types (those known as controlled-release fertilizers), the fertilizer granules are coated with a permeable substance; with each watering, a bit of fertilizer diffuses through the coating and into the soil. Depending on the particular product, the nutrient release may last anywhere from 3 to 8 months.
Some synthetic products are packaged for special purposes; you’ll find spikes and tabs for container plants, for example.
Note that synthetic fertilizers usually do not contain any of the secondary or micronutrients mentioned above―but in most cases, these nutrients are already present in the soil. If a test indicates that some are missing, look for a fertilizer that provides them.
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Organically derived fertilizers typically have a lower NPK analysis (nitrogen, phosphorus, potassium) than synthetics fertilizers, but they feed plants for a much longer period of time. As a result, the impact of organic fertilizers on lawn and plants is usually more subtle.
Organic Fertilizers are materials derived from plant and animal parts or residues. Examples are, Blood Meal, Compost, Bat Guano, Manure, Seaweed, and Worm Castings. Synthetic Fertilizers are “Man made” inorganic compounds - usually derived from by-products of the petroleum industry.
Prominently featured, the N-P-K-ratio is the percentage the product contains by volume of nitrogen (chemical symbol N), phosphorus (P), and potassium (K). A 16-16-16 fertilizer, for example, contains 16% nitrogen, 16% phosphorus, and 16% potassium.
1:1:1 NPK FERTILIZER contains equal parts nitrogen, phosphorous and potassium. It is gentle enough to use as a general purpose liquid fertilizer for indoor plants and trees without burning foliage. NUTRIENT-RICH FORMULA acts as a liquid plant food to stimulate stem vigor, root growth and reproduction.
All fertilizers have a chemical listing of N-P-K. As an example a fertilizer listing of 16-16-16 contains 16% Nitrogen, 16% Phosphorous, and 16% Potassium. Some fertilizers contain trace elements, slow release nitrogen, and organic sources of nutrients.
This label, known as the fertilizer grade, is a national standard. A bag of 10-10-10 fertilizer contains 10 percent nitrogen, 10 percent phosphate and 10 percent potash.
This Hyponex 40 lb.All-Purpose Fertilizer 10-10-10 is great for your vegetable garden, shrubs, trees or flower beds. The fast-release formula feeds your plants for up to 2 weeks.
Commercial growers often use synthetic fertilizer because it speeds up the growth process of their crop. However, overuse of synthetic fertilizers over time can deplete soils of natural microorganisms and nutrients.
Organic fertilizers. Examples of naturally occurring organic fertilizers include manure, slurry, worm castings, peat, seaweed and guano. Green manure crops are also grown to add nutrients to the soil.
NITROGEN 30: Gives you green grass, fast! This water-ready, quick-release formula helps produce more chlorophyll for a faster, thicker, darker lawn. PHOSPHORUS 0: Phosphate-free! For reduced impact on lakes and streams. POTASSIUM 3: To help plants fight off disease and for water retention.
Studies have found that the ideal NPK fertilizer ratio of those nutrients for flowering plants is 3-1-2. (That's 3% Nitrogen, 1% phosphorus & 2% potassium.)
The first number is nitrogen, the second is phosphorous, and the third is potassium. The numbers tell you the percentage of that nutrient in the bag. So,quiz time! If you have a 5-10-5 bag of fertilizer that weighs 10 pounds then 5 percent or one-half pound of it is nitrogen.
SUNBurst 5-5-5 Fertilizer can be applied to all vegetables, fruit trees, nut trees, vines, flowering and ornamental trees, shrubs, flowers, containerized plants, and turf.
Most fertilizers that are commonly used in agriculture contain the three basic plant nutrients: nitrogen, phosphorus, and potassium. Some fertilizers also contain certain "micronutrients," such as zinc and other metals, that are necessary for plant growth.
Synthetic fertilizer is derived from chemicals such as ammonia, natural gas, atmospheric nitrogen, phosphate minerals, and sulfur. A fertilizer manufacturing plant is used to prepare a number of different fertilizer blends.
Commonly used organic fertilizers include composted animal manure, compost, sewage sludge, food processing wastes, and municipal biosolids. They improve soil health and release nutrients to soils gradually.
These nutrients are the three numbers on a fertilizer bag listed in order (N-P-K). So, a fertilizer that contains 5-10-10 means it has 5 percent nitrogen, 10 percent phosphorus (phosphate), and 10 percent potassium (potash). A “complete” fertilizer contains all three.
30-0-10 is a professional quality turf fertilizer for use on all lawn areas including fairways, tees, and other turf. The slow-release formula helps reduce mowing, conserve water and is non-leaching. Guaranteed Analysis: Total Nitrogen (N) - 30%
This Hyponex 13-13-13 40 lb. All-Purpose Fertilizer helps provide the nutrients your plants need to grow. This fertilizer is ideal for your vegetable garden, shrubs, trees, hedges and flowers. The fast-release formula feeds your plants up to 2 weeks.
AVANTAGE (18-18-18) Water-soluble fertilizer, foliar or soil applied. Recommended for the fruiting stages of fruit trees, vegetables and for flowers and ornamentals. Avantage (18-18-18) is totally water-soluble and suitable for all soil types and for all environmental conditions (cold and hot weather).
A very useful formulation for landscaping. DYNAMAX™ fertilizers are special formulations of the DYNA GREEN™ line designed to stimulate luxuriant growth and dark green foliage by supplying the “extras” not found in the standard formulations.
Ideal for vegetable and flower gardens, shrubs and landscape plantings. The quick release formula can be applied every 30 days through-out the growing season to provide primary nutrients to promote plant growth.
Excess fertilizer alters the soil by creating too high of a salt concentration, and this can hurt beneficial soil microorganisms. Over- fertilization can lead to sudden plant growth with an insufficient root system to supply adequate water and nutrients to the plant.
Synthetic nitrogen, now used extensively in conventional fertilizers, helps farmers produce higher yields to feed a growing world population. However, when this nitrogen is not fully utilized by the growing plants, they can be lost from the farm fields and negatively impact air and downstream water quality.
The overuse of synthetic fertilizers and pesticides in agriculture leads to higher emissions of nitrous oxide, a gas that is 300 times more powerful than carbon dioxide. Synthetic nitrogen has also caused water pollution at both surface and ground levels.
Many can be applied directly such as anhydrous ammonia, urea, urea-ammonium nitrate solutions, triple superphosphate, ammonium phosphates, and muriate of potash (potassium chloride).
But organic fertilizers have advantages. They don't make a crust on the soil as inorganic fertilizers sometimes do. They improve water movement into the soil and, in time, add structure to the soil. Organics feed beneficial microbes, making the soil easier to work.
Poultry and animal manures have been used as organic fertilizers for centuries. If used correctly, they remain among the best npk fertilizer options for organic gardeners today. Manures are nicely balanced, providing small amounts of nitrogen, phosphorus, and potassium, in a base of predigested organic matter.
This 0-10-10 NPK rating formula provides phosphorus and potassium to your flowering plants. Potassium promotes stronger plants, bigger blooms, and more fruits and vegetables, while phosphorus helps develop strong roots.
Summary. Low nitrogen and potassium, in combination with higher levels of phosphorus, make 10-20-10 a great choice for gardeners looking to improve root development, homeowners looking for a better root system in warm-season grasses or someone who is growing a newly established lawn in from seed.
NPK 10 - 30 - 20 is a water-soluble fertilizer powder used when transplanting, before flowering or when more phosphate is necessary to plants. It works effectively on almost all types of plants to ensure a more developed root system and rapid crop growth.
Growmore 7-7-7 is a well known balance NPK suitable as a short general feed. Growmore fertiliser offers a multi-purpose planting fertiliser that is ideal for use in the garden. Growmore can also be used on established plants as a balanced feed.
NPK 12-12-17 Grandfield Adfert Fertilizer can be mixed with soil amendments and Humic acid before application. It helps to promote absorption rates of nutrients to increase flowering and blooming strength in crops, landscape plants, ornamental plants, and fruit trees.
BENEFITS: BEST® Ammonium Phosphate 16-20-0: Is a hom*ogeneous fertilizer (hom*ogeneous means that each pellet contains the same ratio of nutrients) to prevent nutrient segregation and insure even and uniform distribution of the fertilizer (no streaking). Contains 13% sulfur to enhance plant color and density.
15-30-15 can be used to remedy phosphorus deficient soils. Plant-Prod 15-30-15 High P fertilizer is recommended at the beginning of growth, as required by many greenhouse crops, in particular by tomatoes and cucumber grown in open ground.
Manure is a complete NPK alternative but is fairly low in terms of the nutrients it supplies to your soil. Manures vary in nutrient content depending on the animal source, but a rate of 1-1-1 is common.
To clear the air, a simple test called phosphate fixation capacity can indicate whether the soil requires phosphorus fertilisation every season. The argument by extension officers that the NPK fertiliser is superior to DAP because the latter does not acidify soils is highly debatable.
A chemical fertilizer is defined as any inorganic material of wholly or partially synthetic origin that is added to soil to sustain plant growth. Organic fertilizers are substances that are derived from the remains or byproducts of natural organisms which contain the essential nutrients for plant growth.
Organic fertilizers. Examples of naturally occurring organic fertilizers include manure, slurry, worm castings, peat, seaweed and guano. Green manure crops are also grown to add nutrients to the soil.
Inorganic fertilization is commonly used by farmers such as the implementation of NPK fertilizer in the form of Urea, SP 36, and KCl. N, P, and K nutrients are essential nutrients for plants, it must always be available in the soil.
Bio Pellets - With an NPK ratio of 10-4-6, these pellets are high in nitrogen. The pellets can be used to enhance the nutrient contents of soil or cocos.
Studies have found that the ideal NPK fertilizer ratio of those nutrients for flowering plants is 3-1-2. (That's 3% Nitrogen, 1% phosphorus & 2% potassium.) So look for that ratio on the label of packaged fertilizers; anything close to a 3-1-2, a 6-2-4 or a 9-3-6 should be ideal.
Excess nitrogen can cause plants to grow excessively and develop overly succulent leaves and shoots, which promotes outbreaks of certain sucking insects and mites. Excessive nitrogen causes fruiting plants to produce relatively more foliage, reducing their fruit production and delaying fruit maturity.
Plants that are almost all leaves need a lot of nitrogen, so look for a fertilizer with a high first number. The higher the number, the more nitrogen the fertilizer provides. This is why most lawn fertilizers are high in nitrogen, with formulations like 24-4-12 or 20-2-6.
IFFCO manufactures NP Grade 20-20-0-13, An Ammonium Phosphate Sulphate Fertiliser. Besides two macro-nutrients (Nitrogen and Phosphorus), it provides Sulphur which is an essential nutrient essential for the growth of plants and aids in chlorophyll synthesis.
Fertilizer potassium is sometimes called “potash”, a term that comes from an early production technique where potassium was leached from wood ashes and concentrated by evaporating the leachate in large iron pots (“pot-ash”).
You can use both organic and synthetic fertilizers. For immediate results, you may need to feed with synthetic fertilizers while adding organic fertilizer blends to rebuild soil health over time.
While organic fertilisers have many benefits, there are some drawbacks that should be considered before using them. One of the main drawbacks is that they can be more expensive than chemical fertilisers. Another downside to organic fertilisers is that they can take longer to work than chemical fertilisers.
Introduction: My name is Wyatt Volkman LLD, I am a handsome, rich, comfortable, lively, zealous, graceful, gifted person who loves writing and wants to share my knowledge and understanding with you.
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