Beginner Gardening: Help! Seemingly heathly Perennials loose/don't flower, 1 by captKirkS

captKirkS wrote:
I planted some perennials in the front yard this dreadfully hot spring because i wanted something that I wouldn't have to replant every year.
My front yard faces the Mississippi south sun and my bed gets 6 hours + during June - August.

Since perennials are somewhat new to me, I just sort of grabbed whatever I found at the local box warehouse as long as it had a perennial tag stating 6 hours or more of sun.
However, I ended up with two that I'm hopeful about: Cheddar Pinks (Dianthus) and Ice Plant (Drosanthemum floribundum).
The Cheddar Pinks lost all their blooms at the store but I figured they'd come back after deadheading. The Ice Plant was full of blooms and opened/closed with the sun faithfully for 1.5 months. It gets a whole lotta sun!!

The Cheddar Pinks never developed blooms until a few days ago when I saw this lone bloom happening. When I planted them, I wasn't sure how to deadhead them so some, I deadheaded randomly at three locations (just below the flower, middle of the stem and base of the stem).

Watering:
We're in a drought with record high temps so I monitor the conditions frequently. I water the Ice Plant once every two weeks if we don't get rain for two or more weeks. I water the Cheddar Pinks once or twice a week under the same conditions.

Soil Ph:
I cannot get an accurate Ph test because the dye from colored pine bark mulch has colored the soil.
However, tests all over the front yard yields a neutral Ph.

Any idea why these otherwise healthy plants won't bloom like they should?

This is a thumbnail image - the readers will be able to see an enlarged version once it is posted.