|NPK = PLANT FOOD SOURCES
|N = NITROGEN - For soils that are nitrogen deficient, treat, manure, weeds, grass clippings, and other garden wastes with CBPA and add the resulting compost to the soil. This will result in a simultaneous improvement in humus and nitrogen content.
|P = PHOSPHORUS - A natural phosphate rock product can be the best source of phosphorus. Phosphate rock is most effective when applied in combination with manure (3 to 5 lbs. of manure per pound of phosphate). Treat the manure with CBPA and work into the soil. Wait 20 to 30 days and work the phosphate rock into the top layer of soil.
|K = POTASSIUM - Sources of potassium include, dead plant material, manure , compost, granite dust, greensand, and seaweed.
|N - P - K and Organic Fertilizers -
|Don't be confused about the NPK numbers associated with organic fertilizers? What
value do they offer organic gardeners? A plant needs nutrients to survive. Most of these are provided by the soil, but soil varies tremendously in nutrient amounts, soil type, pH, and nutrient
|The three main nutrients that have been identified as absolutely
necessary for plants are nitrogen (N), phosphorus (P) and potassium
(K). These three are also known as macronutrients, and are the source
of the three numbers commonly found on organic fertilizer labels. The
numbers found on our Organic All-Purpose Fertilizer, for example, are
7-7-2. This is the percentage by weight of the N, P, and K found in the
|So what's so important about nitrogen, phosphorus and potassium?
|Nitrogen (N) is probably the most widely recognized nutrient, known
primarily for its ability to green up lawns. Nitrogen mainly affects vegetative growth and general health. Chlorophyll, the green substance in plants responsible for photosynthesis, is largely composed of nitrogen. It is also used heavily in new shoots, buds, and leaves. Air contains about 78% nitrogen, but atmospheric nitrogen is not readily available to plants. They must absorb it through the soil. Ammonium and nitrate are both readily available forms of nitrogen, but they are
common in chemical fertilizers and leach heavily and quickly out of the
soil. Nitrogen can be applied organically in many ways, including
composted manure, blood meal, canola meal, fish powder and various
liquid organic fertilizers. Keep in mind that many organic dry
fertilizers are slow-release, helping the long-term nitrogen content
and building up organic matter in the soil.
|Nitrogen deficiency is recognized by the yellowing of older leaves, slowing or stopping of growth. Leaves may drop sooner than expected. Excess nitrogen is recognized by extremely fast growth, resulting in long, spindly, weak shoots with dark green leaves.
|Phosphorus (P) is important for healthy roots and is used more heavily during blooming and seed set. Phosphorus is easily rendered unavailable to plants when the pH is slightly unbalanced. It is released in soil through decomposing organic matter.
|Phosphorus deficiency is recognized by dull green leaves and purplish
stems. The plant is generally unhealthy, sometimes yellowing. Lack of
blooming with lush green foliage may also indicated a lack of
phosphorus. Organic phosphorus can be found in rock phosphate, bone
meal and various liquid organic fertilizers such as fish emulsion.
|Potassium (K), sometimes known as potash, is important for general
health of plants. It is key in the formation of cholorphyll and other
plant compounds. Potassium is also known to help with disease
|Potassium deficiency is hard to symptomize, but plants are generally
sickly, with small fruit, yellowing from the older leaves upwards, and
sickly blooms. Sources of organic potassium include sul-po-mag (sulfate
of potash magnesia, quick release), greensand, and liquid fertilizers
such as Earth Juice's Meta-K.