‘Feeding Orchids – Feast or Famine’ was the title of an excellent talk by Malcolm Moody, via Zoom. Starting with water quality it was recommended that rain water be used, but check the ph is collected from a tiled roof as that could be acidic. Water should be brought to room temperature before use to prevent shock to the root system and if stored for any length of tine it should be covered to slow down oxygen loss. The use of an aquarium air pump to oxygenate water before adding feed was recommended.
Moving on to the feed itself Malcolm recommended using liquid feeds as crystalline products need to be thoroughly dissolved and can re-crystallise in the composts. A chart giving the composition of orchid feeds showed great variation, with few containing essential trace elements. The general advice was to follow the manufacturer’s instruction, and to reduce feeding during the winter months.