Hi Lou, and welcome. It sounds to me as if you might be overwatering the plants. Most garden perennials like a deep watering every few days, then to dry out in between in order to bloom their best. Your 30min. twice daily would keep those plants pretty wet all the time. Soil they're in, could stay soggy in fact.
Now, I'd like to qualify this by saying "it depends" upon where you are and what your soil is like. Could you please fill in your profile with your location (city/state/country not just a zone) so that we can have an idea of what your conditions are right now. eg. if you are in Arizona or Texas and it's above 100deg. and super dry, your watering regime might be ok. Sandy soil will drain and dry much faster than clay or a soil high in organic material.
