Getting citrus off the ground

To make sure his plants are virus-free, this nursery owner never allows the roots to come into contact with the soil. Producing virus-free citrus plants for sale takes rigorous management, says Trevor McKenzie of Nucellar Nursery in Simondium, Western Cape. He produces under the Citrus Superplant Scheme, which means all the plants he grows must be certified by inspectors to ensure they conform to the scheme standards.

SPEEDLING TRAYS 

To prevent any possibility of contamination by viruses, plants must never at any stage come into contact with the soil. The plants are produced in a controlled environment in Speedling trays, with the roots being air-pruned as they poke through holes in the bottom. 

Seeds for seedling rootstock are obtained directly from the scheme, which is run by the Citrus Exchange in Port Elizabeth (Ggeberha). This seed has been tested and certified virus- and pest-free, and treated against phytophthora.

Seven different root-stocks are grown to cover the various planting conditions in the Western Cape.

The seed is germinated in a small, insulated and heated germination room, where conditions are as optimum as possible to ensure a short germination time. This saves on energy costs and allows more sends to pass through the room during peak production times, which is vital for cost-efficiency.