The Sea Bed Cal-Phos product above contains approximately 2.85 % actual Phosphorous (P)
The information below was taken from the Spectrum Analytic "Agronomic Library"
Phosphorous (P) Basics
Functions of Phosphorous
Phosphorous is essential to many plant functions and structures. It plays a role in
- Photosynthesis
- Respiration
- Seed and fruit production
- Energy production, storage, and transfer
- Cell division and enlargement
Adequate supplies of P promote or enhance
- Early root formation and growth
- Greater flowering and seed production
- Fruit, vegetable, and grain quality
- Better growth in cold temperatures
- Water use efficiency
- Early maturation of fruit and grain
The primary functions of P in plants are
- Structural component of proteins, enzymes, nucleic acids, and DNA
- Photosynthesis (production of sugars and starches)
- Respiration (producing energy by oxidizing sugars and starches)
Phosphorous compounds form part of the structure of amino acids, proteins, nucleic acids, and DNA (Fig. 1). It is obvious that without DNA plants cannot reproduce, which means that they cannot produce the seed and fruit that we harvest from many crops. Without nucleic acids plant cells cannot develop or function properly.
Less obvious are the many different roles that various proteins play in the proper functioning of plants. For example, some proteins are essential for the formation and proper function of enzymes, which are involved in many plant processes, including photosynthesis.
Phosphorous plays a central role in both photosynthesis and respiration. Both are exceptionally complex processes, as illustrated by the Krebs cycle (Fig. 2). The Krebs cycle is the second step in respiration, the process within which plants produce the energy needed to exist and grow. Compounds containing P such as NAD, NADH, ADP, and ATP are key components of the Krebs cycle.
The production of sugars during photosynthesis and the conversion of these sugars into energy during respiration enable the plant to perform all other life-functions. When respiration is restricted due to a P shortage, sugars are not converted into energy and they accumulate within the plant tissue. The accumulation of unused sugars leads to the purple coloration often seen with P deficiency. The low energy level within the plants is the underlying cause of the stunted growth typically seen with P deficiency. When energy is low, all plant processes suffer. Flowering and reproduction place a high demand for energy on plants (not to mention the need for DNA in seed production after fertilization). Therefore, adequate P is essential to the process. A plants ability to generate abundant energy becomes more important when it is put under additional stress, such as cold soil and air temperatures.
Phosphate in Composting:
Colloidal phosphate consists of clay particles surrounded by natural phosphate. Total phosphate is around 20% and "available" phosphate about 2-3%. An efficient use of colloidal phosphate is to add it directly to livestock manure in the barn or lot, where the manure acids dissolve much of the total phosphate and the phosphate stabilizes the nitrogen in the manure. Many of the same advantages can be had by adding 20-50 pounds of colloidal phosphate to one ton (two cubic yards) of manure when composting. The ATTRA publication Farm-scale Composting Resource List directs the reader to many useful resources on composting. When direct land application of rock phosphate is the only possibility, spreading rates between 500 and 2,000 pounds per acre are appropriate, depending on phosphorus status, soil acidity, and finances.