The weather has been and will continue to be very hot. This can be stressful for the vines (and for you!). Monitor as needed to make sure the vines and fruit are not lacking for water. We all recognize there is much concern about depleting water supplies and upcoming harvest. Let's hope we get some rain soon.
No unusual levels of rot have been reported and upright dieback symptoms have been reported in beds with a history of the disease or in beds with some sort of heat and/or water stress. Remember that fungicide applications at this time of the year will have a very small impact on field rot infection and upright dieback. Short irrigation periods can decrease canopy temperature by 30-40°F and avoid scalding as long as soils are not saturated and no puddling occurs.
If you plan to do tissue tests, collect your samples from mid-August through mid-September. You can get your samples analyzed locally or send them off to UMass for analysis. Samples should contain no more than the top 2 inches of growth (no roots, soil, runners, or fruit). Collect tissue from vegetative and flowering uprights. You typically need about 1 cup of vine tissue. Do not collect samples when the vines are wet and do not send the samples in plastic resealable bags. Always request nitrogen determinations when you submit your samples.
If you are still applying pesticides (e.g., 2nd application of Ridomil or Aliette for Phytophthora), be sure to observe all needed PHIs. Ridomil products have a 45-day PHI; Aliette has a 3-day PHI. Callisto has a 45-day PHI, QuinStar, Poast and Select are 60 days.
The CCCGA will be holding their annual meeting this Wednesday Aug 17 at the Upland Club in Plympton.
