COCOFIBRE DUST, A NEW GROWING MEDIUM FOR PLANTS IN THE TROPICS

Due to the problems for finding good horticultural substrates in the tropics, a serie of tropical organic waste products are analysed.
Rice hulls, tea waste and cocofibre dust have been studied.

Composting experiments are carried out in the laboratory with a composting simulator in order to optimize the composting process.
This is necessary because phytotoxic compounds are present in the fresh materials.

From the results of the composting simulator and growing experiments, following conclusions can be drawn :

• rice hulls can be composted with the addition of 1 % nitrogen and urea as nitrogen source,

• tea waste is very rich in nitrogen (3.5 %). Therefore mixtures with a carbon rich material as rice hulls and cocofibre dust is necessary,

• cocofibre dust is very high in carbon (> 45 %). Adding 1 % nitrogen to this material gave only small amounts of oxygen consumption which means that the degradation of this material is very difficult.
  Nevertheless the composting period is necessary because of the presence of phytotoxic compounds in fresh material.
  Cocofibre dust of an age of at least 4 months gave no more influence on the growth of sensitive plants that means that the phytotoxic compounds are disappeared.
  For having a good constant growing medium on the base of cocofibre dust a composting period with small amounts of urea is recommendable of at least 2–3 months at an appropriate moisture content.

Nutrient Film Technique and Substrates, XXI IHC

O. Verdonck, D. De Vleeschauwer, R. Penninck

https://doi.org/10.17660/ActaHortic.1983.133.25