- What are Organic Fertilizers?
- What is NPK?
- Single Ingredient or Blends?
- What form do fertilizers come in?
- Are higher NPK amounts better?
- Will I be able to tell if I am feeding my plants the wrong amount?
Organic Fertilizers are derived from plant, animal or mineral resources, and combined with organic matter
Organic Fertilizers are ideal for enhancing soil fertility and stimulating plant growth in a sustainable and environmentally friendly way. Organic fertilizers add nutrients to the soil for uptake by plants and for use by the myriad microorganisms that inhabit healthy, productive soil. Fertilizers are available as single ingredient nutrients or as complete blends with multiple applications.
NPK is abbreviation for the macronutrient combination of nitrogen, phosphorus and potassium
Fertilizers are labeled with numbers that represent the percentage of the three primary macronutrients – nitrogen (N), phosphorus (P) and potassium (K) – that are immediately available in the fertilizer. These elements are listed as the NPK ratio. For example, our All Purpose Mix 4-6-2 is comprised of each primary nutrient, whereas our Blood Meal 12-0-0 is a single ingredient source of nitrogen. Each nutrient plays specific and complementary roles. Very generally, nitrogen energizes vegetative growth, phosphorus produces expansive roots, flowers, fruits and viable seeds, while potassium (or potash) promotes sturdy stems, plus resistance to disease and temperature stress. Most fertilizers will also contain varying amounts of the secondary macronutrients – calcium, sulfur and magnesium – along with trace elements or micronutrients that also play essential roles in plant nutrition.
It depends on what your plants need
Single Ingredient Fertilizers are used for specific plant needs and in certain stages of a plant’s development. For example, a high nitrogen source like Feather Meal 12-0-0 is used when heavy feeding plants, such as corn, need an additional boost early in the season. To promote big, beautiful blooms on your flowering plants, utilize a high phosphorus fertilizer, such as our Seabird Guano 0-11-0 or Bat Guano 0-7-0.
Fertilizer Blends, on the other hand, are used for more general needs around the home and garden. Our All Purpose Mix 4-6-2 is ideal for vegetables, flowers and trees as well as houseplants. A great advantage of multipurpose blends is that they save gardeners time and labor by offering a variety of single ingredients pre-mixed in exact and balanced proportions.
Organic fertilizers are sold in three forms: dry, water-soluble powder and liquid
Dry fertilizers come in several textures: pulverized powder, meal, granulated and pelletized. They can be broadcast or spread over garden soils and lawns, and also incorporated into potting soils to provide nutrients to transplants and new plants. Dry organic fertilizers generally meet plants’ needs by releasing their nutrients
Soluble powder fertilizers begin to break down immediately, so they can be applied to the top few inches of soil for quick release, or transformed into a liquid fertilizer for foliar feeding or for use in irrigation systems. A foliar tea can be made by soaking the fertilizer powder overnight in a cloth bag suspended in a container of water. In the morning, empty the residue that is left in the bag around your garden, and pour or spray the richly colored liquid on garden plants.
Liquid fertilizers usually come as a concentrate and need to be diluted with water before using in your garden or to feed your houseplants. Both teas and dilutions can be applied with watering cans, hose end sprayers or through irrigation systems in a method known as fertigation. Tea and liquid soil feedings work best after a light rain or regular watering when the soil is more absorbent. Teas and liquids can also be applied directly to the leaves and bark of plants and trees using the above mentioned foliar feeding methods. Foliar sprays can be more effective than soil applications in correcting nutritional deficiencies and treating stress related problems under some conditions. For best results, spray early in the morning and when the air temperature is below 85° F.
No, higher NPK amounts don’t always mean higher quality or more effective fertilizer
To someone accustomed to the higher NPK ratios of chemical fertilizers, such as 18-51-20, the modest amounts occurring in organic fertilizers may appear inadequate. However, nothing could be further from the truth; organics break down at a slower rate. Nitrogen supplying organic fertilizers contain insoluble nitrogen that releases slowly with greater effectiveness than conventional fertilizer, and reducing the need to reapply fertilizers as often in order to maintain soil fertility. Organics minimize the possibility of “burning” plants with concentrated chemical supplies of nutrients. They improve overall soil health rather than degrade it, by encouraging soil microbial life to flourish. Since organic fertilizers last longer and release their nutrients slowly, their long-term NPK amounts will be greater and more beneficial than what is shown on the label.
Yes, and luckily, the signs that your plants have a nutrient imbalance are easily recognizable.
Too much nitrogen produces dark green foliage, few or no flowers or fruits and burnt leaf tips. Too little nitrogen produces light green to yellow leaves and slow growth, especially in the lower leaves of older plants.
An excess of phosphorous is rare, yet when it does occur symptoms are similar to an excess of nitrogen. A phosphorous deficiency is revealed by deep green, red or purple leaves, few blooms and fruits, yellowing bottom leaves and stunted growth.
Potassium toxicity will create nitrogen, phosphorous and trace mineral imbalances. Potassium deficiency produces very tall plants with weak stems as well as leaf tips and edges turning yellow, then brown later.
Too much calcium and magnesium increase potassium problems, and can also inhibit reciprocal uptake of each other. Too little calcium will cause young leaf tips to die back, blossom end rot on tomato fruits, short roots, stunted growth and rotten plant centers. Magnesium deficiencies show up in leaf tips turning brown and curling upwards in a hook shape.