Question
My parents' home is constructed of local quarried limestone in Minnesota.  Would you consider this to have any potential for making the soil at the foundation too base?  Do you think I should make any attempt to reduce the pH there?  Most of the evergreens look good, there are a few flowering shrubs that don't.  What would you advise?
Thanks.  

Answer
Your concern about the Limestone foundation is unfounded, my friend.  Unless the Limestone is pulverized and incorporated into your Soil, it cannot affect pH or alkalinity.  Even deliberately applied, powdery gardener's Lime moves very little into the Soil profile after application, and takes years to alter pH.

Mulching your foundation Evergreens with Peat, Wood chips and Coffee Grounds will enrich your Soil and tilt the pH ever so slightly toward the Acid reading these plants love.  A Soil test however should precede that step.

Flowering shrubs may simply not be getting enough Sun.  Take a good luck -- in the Summer -- and see how bright it is.  Blooms require energy, and plants get that straight from the sky.  Take note of the Phosphorus reading when you test your Soil; these plants need it to build flowers.  Can't do that without it.

Finally, with regard to your poor show of flowers on certain shrubs, make sure you are not pruning them incorrectly.  A badly timed prune project can end up cutting off next season's flower buds, leaving few if any to bloom.  Know your pruning schedules.

Thanks for writing.