Composting tends to neutralize pH and decrease plant toxins. A
handful of hulls to a bushel of leaves is fine, but I like the idea
for the hulls to rot for a year before adding to the compost bin. I
do that with sawdust (I have an endless supply of sawdust). The heap
of sawdust gradually turns gray near the bottom and that's what I use
for mulching my blueberry bushes.