Some of my raspberry canes are suffering from a yellow leaf problem. They turned this color in mid Spring when they grew out their new leaves. There are about 3 canes like this sprinkled in among others that appear normal. Does anyone have a clue what might be causing this?
That is likely a virus. It could also be some nutrient deficiency or excess. I would pull them out pronto, trying to get as much root as possible as well. I don't think there is any treatment besides removal. It is also hard to keep to keep it from spreading.
Scott
You might also try Epsom Salts. Yellowing with veins remaining dark can mean a magnesium deficiency. If that's the cause, improvement should show within a week. Yuska
I don't think it is magnesium deficiency, the outer edges of the leaves stay green with that. But it would not hurt to apply some fertilizer -- I would use an organic fertilizer with all the micronutrients to cover all your bases there, in the off chance it is a nutrient deficiency of some sort. You could also have too-high pH or salt poisoning.
I still feel the #1 problem is virus due to the splotchiness and for that you should pull out the bad plants now since it could already be too late. My strawberries are ruined because they got a virus which I could not contain. I think I will get one more year out of them and then I will have to find a new spot.
Scott
Thanks for your input. I think the safest course of action is to dig out the affected plants and also spread some fertilizer for the ones I leave in, maybe kelp meal, and I'll try the epsom salts too. It is unlikely my soil in too alkaline, as soils in the Pacific Northwest tend to be naturally acidic and I did not lime the spot the berries are in. If the problem was the magnesium deficiency, the remaining plants should then be fine. And if it is a virus, hopefully it will not have spread.
Out of curiosity, how are such viruses contracted? Are they soil borne, air borne, or insect borne? I have had raspberries in that location for 7 years with no prior difficulty. I dug a new row 2 years ago and planted with a different variety from a nursery. They did fine f the first year (autumn bearing) then turned brown and died the second summer, except for one plant on the end that is perfectly healthy this spring. This appears to be a completely different problem than the yellow leaf issue. My second row is currently planted to cabbages instead of raspberries, as I'm not sure I should plant berries there again. Hopefully my whole patch is not doomed.
I am no expert on raspberry viruses, but I know some of them are spread by pollinating insects. They are also a major issue and are the way most raspberry plantings get done in. It is also a reason why it is important to get plants from a top nursery and not your neighbor, then you are starting over in the virus war. I always buy my raspberries from Nourse because I completely trust them on that front. For my strawberries I made the mistake of getting a couple plants from someone and four years later those two plants have sickened my whole bed.
Scott
