My raspberries hate me too
And my happy raspberries that have done fine for the past few years have something going on. What is up with this crazy dark green leaf curl chaos? And the browning of the leaf? And is it possible Japanese beetles are eating them too (no sign of beetles, but I have some leaf chomping going on.) Overall the bed is doing ok but I am worried that something is deeply wrong and I will have to scorch earth my bed. Help!
Boulder County Colorado
Thank you for contacting the Colorado Master Gardeners. Sorry to hear about your raspberries. They do look a little unhappy! I'm sending you a couple of links from our CSU Extension about raspberries, just for general information. I am also sending you a link on diagnosing raspberry problems. It has been very hot and dry and Spider Mites are common problem for rasberries in Colorado that occurs in that kind weather.
It appears you have some bronzing of the leaves, as mentioned occurs with spider mites. The first sign sign of Spider Mites would be small yellow spots on the leave and I believe I can see a couple of yellow spots on some of the leaves in your picture. This causes bronzing or browning of the leaves. The best way to treat Spider Mite is to provide adequate water, and fertilizer, to maintain healthy plants. Also spray the underside of the leaves to physically remove the mites.
As for the curling, I'm wondering if that might possibly be because of lack of water during the heat? They do not appear to be bronzed or brown. Not all leaves are curled and for the most part newer leave look healthy.
If have any further questions don"t hesitate to contact us with more information on the care of your raspberries. Look on other leaves and see if you can identify any yellow spots or sign of insects. I hope this has been helpful to you. Good Lick with your raspberries! Jeanine