Two blueberry problems?
By way of brief background: 3 or 4 years ago I planted some rather small starter blueberry bushes in my backyard here in Vermont. They've really struggled - the first winter some deer or something got in there and gnawed them all down, and the first full summer my pH was probably too high, then that winter they got damaged again. I have all of this (I think) under control and they had been looking good until I just noticed a couple of things...
1. They are growing vigorously, lots of new shoots and leaves. I had noticed a pattern where the new growth would be red/yellow and then green up, which I believe is normal. But now I'm seeing some leaves that look more reddish yellow than normal, and some seem to be yellow with green veins, which I believe is a sign of iron deficiency caused by high pH.
Our soil is naturally rather sweet and I've been trying to adjust for this by mulching with peat moss and using ammonium sulfate. In fact, I've used quite a bit of ammonium sulfate so I am not sure why this problem is happening... unless it is due to the high amount of rain we've been getting. Any ideas? I could post pictures if that would help.
2. One plant is not thriving -- it's dying. The leaves are turning purple-brown on the edges and then falling off. I have no idea why as this isn't happening with any others. Thoughts?