Poor pollination and very low humidity during pollination can cause crumbly fruit. Symptoms generally do not recur the following year.
![Three blackberries lined up on paper towel. Blackberries have larger drupelets irregularly distributed on the outer edges of the fruit, and large clusters of small drupelets. Small drupelets are one-third of the size of the large drupelets.](https://blogs.cornell.edu/berrytool/files/2020/11/poorpollination_rasp-300x225.jpg)
More information:
- Poor Pollination in Raspberries – University of California
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