Sunflowers will provide visuals up until it gets cold (or they seed out). They're drought resistant so flowering in August (for me) only requires deep watering occasionally. I just water them in hot weather when I'm outside watering other things. Mostly, I just left them alone once the taproot seemed established. You can make subsequent sowings. Varieties seem to be either 80 days to 120 days for maturity. Last year I had several that succumbed to disease causing them to die back to the stalk. They came back with multi-flowers and put on quite a show and tiny seeds for the birds.

I have not started this year's, yet. Probably this week.

You can sow them forever. The DTMs on the packages are estimates only and I have found many varieties flower much earlier here in our heat than the DTMs indicate. (This is true of many other kinds of annual flowers, herbs and veggies too.) I've sown sunflower seeds as late as early August and had flowers in the fall before frost. In a good year with adequate rainfall my sunflowers will form seeds, the seeds will fall to the ground and a few weeks later the seeds will germinate and give you a new round of plants. In addition to the sunflower seeds I plant, we have a couple of kinds of native sunflowers, including Maximilian's sunflower and they grow fine with no help from me. I don't even water them. Sunflowers are about the easiest thing on earth to grow. Sadly, deer will eat them....the flower while it is in bloom or after it has formed but not yet opened, the seed head, leaves, stems, etc., so how many sunflowers we have in bloom in any given year will depend on how hungry the deer are.

no. they'll be fine