Substrates for soil-less Disa production

Abstract

The effects of different substrates were investigated as root media for soil-less Disa production. In a first study, tissue cultured plantlets were hardened. In a second study, hardened plantlets were grown to the early flowering stage. In both cases, a diluted Cymbidium nutrient solution was used to fertigate the plantlets. During hardening, plantlets developed best on sphagnum moss with a relatively high water holding capacity, low salt content and high ammonium level. When hardened plantlets were grown to the early flowering stage, biomass accumulation was better on organic substrates than on Hydroton® clay aggregates. Growth and flowering on an acidic peat substrate were significantly better than where the substrate pH was raised with agricultural lime. The possibility that decomposing organic material may produce substances, beneficial to Disa growth, needs further investigation.