An Orchidist's Miscellany


 A number of organic fertilisers, such as the fish and seaweed preparations, on analysis, are found to contain relatively low concentrations of useable nutrients. Many farmers and growers are convinced that good results can be obtained from their use, greater benefits than would be immediately apparent from the elements they contain. Some research indicates that per unit of nutrient, they are generally more expensive than supplying that nutrient compared with inorganic fertilisers. It has now been suggested that much of the benefit seen to arise from the organic fertilisers arises from the fact that they may contain a hormonal agent which acts as a growth stimulant. The presence of this agent largely produces the results seen from the use of these products.

Vemon Stoutemyer, in The Orchid Advocate of January/February 1983, discusses chemicals which can produce these benefits. One of a number of such compounds is a peptide known as an 'epidermal growth factor', which is found in some organic fertilisers, and which is known to promote cell division, protein formation and wound healing in both plants and animals. Soutemyer notes that when this material was applied to some sorghum seedlings, increased growth (10 - 12%) was produced. The use of dried blood (used as a nitrogen source) during the warmest months of the year, has been observed to produce results better than that available from alternative (inorganic) nitrogen sources,
this material now known to obtain this epidermal growth factor.

Little hard scientific proof appears to be available, although there are many growers who believe good results are obtained from organic fertilisers, especially during the warmer months of the year. Increased interest is being shown in this sphere, and perhaps in the next year or so we will see some conclusive evidence of the benefits from such products. Perhaps there are even some of our own growers who may wish to comment on their experiences with the organic fertilisers.

Site established 9th May 1998