Wet spring conditions are ideal for Psa build up and infection of young tender growth. Growers must maintain full spray cover over the season, particularly prior to, or directly after high-risk weather, on all varieties.

The online KVH Psa Risk Model can help with this and should be used to plan spray timings. The model is a weather-based tool that uses actual weather station data and weather forecast information to provide customised access to weather and disease interpretations.

There are several spray product options available – be sure to meet all user guide requirements. If applying bactericides ensure there are no flowers present in the sward or on vines. KVH has produced a fact sheet covering spray products and recommended timings, key points on pollination and preflower girdles. Copies are available here and at upcoming Zespri spring field day events.