I planted 6 blueberry plants today, in a hedge along the south side
of my house. My experience with blueberries comes from planting a
couple of plants back in the middle 80's. Both died, because our
underlying bedrock is limestone, and we have a pH of around 7.5

I figured I'd get some aluminum sulphate, elemental sulphur, or
ammonium sulphate. Trouble is, none of the garden centers, big stores
or home improvement centers around here seem to carry any of these.
Many of them have bags of lime, however, which I can't figure out why
anybody around here would use. (soil is already naturally alkaline)

I've tried K-mart, Kroger, Lowe's, Home Depot, Meijer.

Can anyone recommend a chain store that carries one of these? Little
garden centers around here are no longer in business.

Thanks!