Applying copper after harvest
It is highly recommended growers apply copper immediately after harvest, with full winter rates as per the KVH Recommended Product List providing maximum protection of fruit stalk and leaf scars from Psa.
Studies suggest movement of product into fruit stalk scars occurs much more readily immediately after harvest versus sprays applied a week later.
Where leaf condition is good and risk of spray drift to unharvested fruit is managed, Actigard can be tank-mixed with copper to provide a dual mode of protection as further leaves fall. Botryzen and the soil root drench KiwiVax (both products with BioGro registration) can also provide benefits, particularly in lower Psa risk situations.
The KVH Psa Risk Model shows moderate risk for most kiwifruit areas through next week and recent leaf spotting seen on outside rows of some Hayward kiwifruit blocks provides evidence that innoculum levels are on the rise. Similarly, cane dieback and cankers in harvested gold blocks indicate potential reservoirs of infection.