Hey Y'all,

I'm hoping y'all might be able to identify what exactly is happening to these plants of mine. When I bought them, from a reputable nursery with whom my family has dealt with for years, the two were doing great. No sign of any problem. I come home and plant them.
Fast forward a week. One has absolutely given up the ghost for reasons unknown. The other was doing well but has now begun to show yellow edges on some of the leaves that become spots towards the interior of the leaf. Whatever it is, it can't be good.
Do any of y'all know any potential suspects? Please help me out. Saying I am a novice gardener would be to flatter me.

THANKS!
Pano

PS The soil here (Baton Rouge, La) varies wildly. Where I am, on what was once the banks of a considerable river at some point way in the pre-Columbian past, is very 'clay-y.' I don't have the word. It being a nature made levee, it's natural that it be so. How can I work around that? I mean it holds water like a punchbowl and of course clay isn't great for most plants. I can get around the second problem, it being bad for most plants, bu putting in a lot of quality store bought soil. The drainage problem I can't tackle outside of a massive earth moving project. Any ideas? I'm creating a butterfly and hummingbird garden - are there any plants that fit that category that like/can live in clay and/or tolerate being in a lot of water (it's roots i mean)? I'll repost this rather long post script in another area of the forum.