I live in Phoenix and it has been extremely hot as of late. Over the past month or so (June-July) my Baby sun rose ( Aptenia cordifolia) has exhibited a yellowish hue to the many of the main stems and new leaf growth are yellow/white. During a rain storm, a couple of weeks ago, they greened up for a few days but soon returned to the description above. The plants are under a sun sail and only get direct sunlight in the early morning. A couple of months ago I placed a miracle grow plant food spike in each planter and recently added another. I typically water about every other day/ I was wondering if anyone may have some insights?