raspberry bush diagnosis
Is this vercilium wilt? I ordered new plants one year ago and removed the old. The old plants had yellow leaves and the fruit was crumbly and a small size. This is my second year with the new plants. The leaves on the bottom of the plant turn yellow and brown in color and drop off. About 10 days ago I added to the soil chelated liquid iron and a 10% nitrogen, 10% phosphate, and 10% potash to the soil. Most of the plants are at a height of 4 feet to 6 feet high some are around 3 feet tall. We had an infestation of rose Shaffer beetles this spring I was able to hand pick them off. Should I test my soil for any thing?
Delta County Michigan
Probably not verticillium. That disease causes rapid death of the whole cane at once rather than lesions at the base of the canes.
More likely this is cane blight. See the following publication.
Testing your soil is a very good idea particularly information about the potassium level and the soil pH. Depending on where you get your soil tested, you may not get information on the nitrogen level in your soil. The pale leaf color may be a sign that your nitrogen levels have been low. Watch to see if your recent nitrogen application helps to regreen the leaves as an indication that your soil nitrogen has been low.
Crumbly berries in your old planting may perhaps be due to a virus infestation.