I planted 4 American variety of elderberry this spring. I amended my soil with peat, steer compost and coir fiber. Our last soil test prior to planting showed 7.2ph. We also have high potassium in water.
They have all been happy vigorous growers till last week. I found brown leaves and now curling up. Please help. What am I doing wrong?

New plants need plenty of water with out getting too soggy. Try watering at base of plant in the early afternoon to allow water to soak in before the sun goes down.