If you're new to gardening, it might save you at least a little bit of grief to know this: with every success in a garden comes a failure Even seasoned gardeners know how it feels to carefully tend a plant only to have it fail to thrive. Some just throw up their little branches in surrender and commit planticide. Under the harshest conditions, like the heat wave and lack of rain we've had lately, even formerly healthy plants can give up the ghost if not handled perfectly. Look at the two pentas above. They are the exact same plant, pre- and post-heat stress. It's my fault - I didn't harden them off enough before I put them out to get sun to continue producing blooms - and I left town for two days and they got too dry. I also didn't mulch the pots, which left them more vulnerable to the heavy prevailing winds that blow through our back yard, especially since a neighbor recently cut down trees along the fence line that once softened the wind. It makes gardening more challenging, but the good news is there's more breeze when you're sitting outside!
Another tip: when a plant label says full sun, always think of that followed by (except in Southeast Texas). Our sun is too much for most plants, especially in the afternoon.