Conditioning coco-peat as a greenhouse vegetable growth medium
Abstract
Soilless culture is a technique for crop production using no soil. It offers earlier growth and higher
yield. Coco-peat, known for its soilless properties, stands out as an excellent growing medium due
to its favorable pH, electrical conductivity, and other chemical attributes. However, it is important
to acknowledge that its exceptional water holding capacity can inadvertently result in an
imbalanced air-water relationship. This, in turn, may lead to reduced aeration within the medium,
affecting the diffusion of vital oxygen to the roots. Therefore, the main aim of this work was to
condition coco-peat by incorporating coarse materials (sand, pumice, and coffee husks) to improve
the physio-chemical properties that meet the requirement of plant growth. These properties include
moisture content, water-holding capacity, pH, EC, and porosity (both total and air-filled) and were
determined in the laboratory using the Oven method by drying between 105°C and 110°C,
measuring cylinder method, pH meter, EC meter and measuring cylinder method respectively. The
moisture content values ranged from 1.2 % to 30.07 % for different soilless types, the lowest value
of moisture content (1.2 %) was found for pumice and the highest value of moisture content
(30.07%) was obtained for coco-peat. The water holding capacity and porosity values ranged from
12.87 to 74% and 42.97 % to 85.13 % respectively for different soilless media. For the mixtures,
each material improved the Water Holding Capacity of coco-peat differently and the percentage
of Water Holding Capacity for the mix ratio of each combination close to that of soil (51%) was
considered the best, 60:40 for both coco-peat to pumice and coco-peat to coffee husks with whereas
40:60 for coco-peat to sand gave the desired. Based on agronomic effect evaluation, the coco-peat
and pumice combination proved to be the best favorable medium with spinach having the highest
number of leaves and leaf area, followed by coco-peat and coffee husks and then coco-peat and
sand. Results of this research indicated that certain physical properties of coco-peat can be
improved through the incorporation of coffee husks, pumice, and sand.