My Malling Jewel raspberries are coming to the end of their fruiting season. Does anyone know what causes a black tar-like substance and general blackening of the fruit? The first pickings were fine, but now 90% of the fruit are almost black all over or have a thick tar-like substance on one side. Such a shame as the harvest would have been really good. The canes were planted early last summer and grew very well. The finished canes will soon be cut down and the new growth tied in. Is there anything I can do to prevent this happening again next year? I have googled extensively, to no avail.
Thanks -
Blackened raspberrries
Moderators: KG Steve, Chantal, Tigger, peter
Hi Tricia. I'm sorry no-one has replied so far to your query, though it seems that a lot of people have looked at it. I've looked up all my reference books and can't find anything that equates with the symptoms you quote. Are you a member of the RHS? They have a very good advisory service for members. If anyone can help, they ought to be able to.
Thanks Ken for your response. Someone on another forum suggested it could be sooty mildew, but that they had not heard of it affecting raspberries. I'll check it out when I cut the canes down because I can then see better - right now the new canes are getting in the way. I have had quite a good harvest and have over 3 lbs frozen for future use, so I'm not too unhappy. Just hope it doesn't happen again next year!
Tricia