One of the fundamental qualities of any good organic system is it’s ability to, not only exist alongside a flourishing natural ecology, but to utilise and enhance this potential powerhouse of stability and health.
The term ‘protected’ however immediately suggests a very different sort of cropping system. A degree of control can be exercised over environmental influences, which are tipped in favour of the crop. This inevitably leads to a strategy regarding the internal ecosystem and its interaction with the external.
Combining border controls with introduced biological agents may effectively regulate the establishment of pests in monocrop systems. However in diverse and continual cropping systems there is no ‘down season’ clear up and the balance of pest, predator and parasite has to be permanently balanced in favour of a viable harvest. Maintaining a healthy biodiversity inside as well as outside the greenhouse is needed to regulate a stable state of play. Examples and strategies for encouraging this, as well as situations where success has been varied, will be presented using case studies from the 0.7ha glasshouse at Hankham Organics as well as other mixed cropping protected systems.