I have three black raspberry plants in my garden that look healthy and produce flowers but have not produced berries. I have attached a photo taken June 9. I’m in northwest CT, zone 6a, ecoregion 58.
The plants were originally growing wild in my yard and I dug them up and moved them to my garden about 4 years ago. They have always looked healthy and grown vigorously during the spring and summer. I have pruned them back every fall.
I have five other black raspberry plants in my garden which I purchased from a nursery last year and they seem to be developing berries normally.
Is this caused by a virus? Or some other pathogen? Any suggestions for what I can do about it?
Wild black raspberries are frequently self incompatible. Rainy weather during the bloom may have prevented cross pollination from the other varieties. Some of my Niwot did the same thing on some flowers this spring, even though it is supposed to be self compatible. We had lots of rain during bloom.
Both very good answers. I would like to add it may be a Boron deficiency, so you could try adding Boric Acid or Borax at a rate of 5grams per square metre or 1 teaspoon per square yard, dissolved in 5l or 2gallons of water.
Thank you. They have never ripened berries in the four or so years since I moved them into my garden. I am not certain if they ripened berries before I moved them.
Unfortunately I don’t have a photo of the flowers. I didn’t notice anything unusual about the flowers, but I wasn’t looking at them critically at the time so I might not have noticed something subtle.
I had not thought to look at the stems. What part of the stems are you interested in? The canes or the lateral branches?
I don’t know if they produced fruit before I moved them.
Hi, Is your soil sandy? if it is, then there is a good chance it is Boron deficient. You will have to send a soil sample to a lab to get it tested for Boron.
Testing and then doing an accurate calculation of how much of an amendment to add is very important, especially when dealing with boron. There have been some great posts on the forum assisting specifically with that one. Logan Labs has very comprehensive testing abilities.
