Hello Andee, happy to help.

Hard water has nothing to do with the alkalinity of your soil. Most of your area of Minnesota has alkaline soil. Your pH reading is pretty close to neutral which is 7.0. It's always a good idea to check on a plant's pH requirements to be sure it'll grow successfully in your soil. But sometimes pushing the envelop doesn't seem to affect a plant that requires more acidic soil.

Good-luck!