Q&As/Fruit Trees & Berries/Brown Rot on Apricots
This year, on our North Otago lifestyle block, many of our apricots are displaying a small brown spot, which quickly turns into a soft rotten spot. I have sprayed a copper spray in the spring as a preventative for fungal disease and leaf curl issues which have affected my peaches in the past. What could cause this brown soft rot? Is there a way we can prevent it or is it mainly related to the colder, cloudier season we’ve experienced this year?
Apricots are particularly susceptible to Sclerotinia fructicola (brown rot), especially if there is significant wet weather in the early part of the growing season.
Both a winter and pre-blossom spray of copper compound are your best weapons to help prevent outbreak of brown rot. However, this is no guarantee of clean fruit. Garden hygiene should also be practiced by removing all rotten fruit where possible, and burning branches/leaves from your winter pruning.
Try a pruning technique to ensure there is free air movement through the tree. The less air movement you have around a plant, the higher risk of humidity and more brown rot. This may involve sacrificing some potential fruiting wood, but could improve the quality of the remaining fruit.
Another product to try is Daltons Organic Bio-fungicide Powder which can also be used as foliar spray to help protect against diseases (apply at 5 day intervals). There is no with-holding period after application.
You could also try contacting commercial apricot growers in Central Otago who have experienced similar problems to see if they have found a solution that works.