Floating cultivation helps reduce the pressure on arable lands by turning the flooded and waterlogged areas into productive ones .
A pilot study was undertaken at RARS, Kumarakom, Kerala Agricultural University on open water culture of seasonal vegetables by utilising water hyancinths as seed beds in floating rafts for vegetable farming.
Seed beds Bamboo poles were used to fix the seed beds in position to avoid damage due to water ripples or drifting. The average dimensions of the seed beds were 5.7 m (L) x 1.8 m ( B ) x 0.7 m (H). Within this area dense water hyacinth is allowed to stand on and more of it was piled up to make it compact.
The duration or stability of the floating bed depends on the first layer, which remains at the bottom. The length and width of the bed can be decided by the farmer.
Though the bed has no definite size, small sized bed is easier to manage and better for crop production. The thickness depends on the duration of crop as it needs to float for the whole time.
Red Amaranthus (Arun red variety) was transplanted on a thin layer of coir pith compost over the bed. It was spaced closely at a distance of five centimeters between plants since open water culture permits trapping of maximum solar radiation.
Application of either 19:19:19 at rate of one per cent or supernatant filtered cow dung slurry was sprayed at weekly intervals for nutrient requirement.
No pests/diseases were noticed. The crop was harvested in 60 days. A yield of 17.8 kg was obtained from a single bed (approximately 17.5 t/ha).
Floating beds Floating beds are mostly made of water hyacinth, a very invasive weed that doubles in area within ten to fifteen days.
These type of experiments provide a means of using the weed in a beneficial way viz., reducing breeding grounds for mosquitoes, improves free water movement and navigation, facilitates open-water fishing etc.
(Dr.Vandana Venugopal is Associate Professor (Agronomy) and Dr.A.V.Mathew is Associate Director of Research,Regional Agricultural Research Station, Kumarakom, Kerala Agricultural University, email: vanjanil@yahoo.co.in, mobile: 098475814726.)
