Agri Kultuur May / Mei 2015 | Page 21

• Also, many hydroponic plants require different fertilizers and containment system. Harvesting In general vegetable crops are perishable and their shelf life and quality depend on number of actions. Such actions include: • Pick at the right stage without damage to the plant. • Pick early in the morning or when it is cool. • Keep picked vegetables out of the sun. • Handle carefully. • Store them at the right temperature (depends on crop). • Use the right packaging (depends on crop and market). • Transport with care. Pests and diseases The optimal growing conditions for plant growth also provide favourable conditions for the development and spread of diseases and pests. Hydroponic producers are thus faced with the challenge of maintaining conditions optimal for plant growth but not for disease or pest development. This balance is often very difficult to maintain, and systems must be managed carefully. It is important for a producer to know what pests or diseases are likely to become a problem. Steps can then be taken to reduce the possibility of the pest or disease entering the greenhouse and gaining a foothold on the plants. Tips to prevent spread of diseases • The most important tools are knowledge and dedication • Several cultivation practices can prevent the spread of disease (e.g. crop rotation) • Sanitation, i.e. cleanliness inside and outside the greenhouse or planted area as well as all persons entering the planted area. Acknowledgement: Guide to hydroponic vegetable Production (Department of Agriculture, Forestry and Fisheries) http://www.nda.agric.za/docs/ Brochures/prodGuideHydroVeg.pdf