The blackberry season just a few days to weeks away, depending on your location. Some of the more common problems that are likely to be seen are:
1. Cane blight. This is one of the most common diseases in blackberry plantings. The tips of the floricanes are necrotic and have a brown/silvery appearance. The canes became infect last year when they were primocanes and were tipped. The wound created by tipping allowed the disease to get into that large wound. To minimize the infection it is best to tip when the canes have a very small diameter. More information here:
http://teamrubus.blogspot.com/search?q=cane+blight
2. Viruses. This was one of my first challenges that I met when I started at NCSU. Back then, several new plantings were riddled with virus symptoms. Thanks to a clean plant program, from tissue culture to nursery, to institution of improved cultural practices, viruses are not as prevalent now. More information here:
http://teamrubus.blogspot.com/search?q=virus
3. Poor fruit set/fruit not ripening. This could be a result of a number of things. Poor pollination during flowering, rain during flowering, but more likely this year to injury to the flowers during the spring. Some fruit never developed as is seen in the first image. You can see in the second image the damaged and not damaged flowers. Those that were damaged will not develop into fruit. For more information on damage from cold, click here
http://teamrubus.blogspot.com/search?q=freeze+injury
4. Leaves suddenly wilting on floricanes. This can be due to a number of things, winter injury, wind damage, crown borers or rodent damage. Here is a link for more information. Picture of wilting raspberry floricane courtesy of Kira Chaloupka.
https://blogs.cornell.edu/berrytool/raspberries/raspberries-only-floricanes-are-wilting-while-primocanes-appear-healthy/
5. Orange spots on canes, also known as Orange Felt or Orange Cane Blotch (
Cephaleuros virescens). This occurs in warm humid fields in the central, eastern and southern parts of NC. It is also in other states in the south. It is a parasitic algae, so even though at first glance it looks like a disease, it is not. Here is a link with some more information.
http://teamrubus.blogspot.com/search?q=orange+cane+blotch