By Caine Thompson, Viticulturist, Mission Estate
In Hawkes Bay during the early summer period we often battle with powdery mildew as the conditions are favorable for this disease. This season has been no different, with high pressure conditions being persistent.
With only sulphur for powdery mildew control under an organic management program I was very concerned about the control we would get.
What has been surprising to me is the level of control we have received under an organic approach, which I’m really pleased about. We also didn’t spray any more frequently than what we did when compared with a conventional program, which I thought we would have to do. From the monitoring that Fruition Horticulture completed for powdery mildew, they reported that the organic program had slightly better control of powdery mildew. This difference was small but was the same trend across all three varieties in the trial.
We have had another cultivation pass which is three for the season for the Pinot Gris and two for the season for the Sauvignon Blanc and Chardonnay. The conventional blocks have recently been weed sprayed. With the conventional Pinot Gris block we have noticed a significant vegetative growth response when compared to the organic which has been interesting to see. The response has been so significant that we have had to trim the conventional block again with the nets on to control the growth.
All blocks are through veraison. There were no noticeable differences between timing and duration of veraison that I noticed between the conventional and organic regimes.
All blocks have been netted and maturity sampling has begun. We have a student from EIT that has been trained in maturity sampling who is collecting brix, Ta and pH and berry weights for each variety and each growing regime as we approach harvest.
Before harvest Fruition will do the final pest and disease analysis. Mission will do the final yield analysis from the blocks and maturity analysis from the harvest samples.
As we approach harvest all blocks are clean and looking in good condition leading into the last month before harvest. Once we have all of the pest/disease, economic, fruit quality and yield data we will present the information in a report form which will then be presented at an industry field day. We wait in anticipation for the harvest ahead and I’m looking forward to seeing how the blocks perform in the last month of the season.