The classic symptom of potassium deficiency is browning/drying around the
edges of leaves. Left unchecked, leaves will turn yellow, wither and fall
off. If you are having a drought, it is logical that potassium would become
unavailable. More than likely, your leaves are exhibiting symptoms of
several nutrients going out of solution.
--
Jim Fruth
Brambleberry Farm
Pequot Lakes, MN
www.bberryfarm.com