Q.trying to get shasta daisy to grow
This is my 3rd year at trying to get shasta daisy to grow in a spot next to the steps on my deck. It’s on the south side, all sun. Everything else I grow in that bed is thriving but they keep dying. Any ideas as to why or what I should do or perhaps plant something else?

Nursery plants and they lasted most of the summer but never came back. although I did find a little sprout of one coming up. I water them every week at once depending on the rain fall.

I have just a few questions to help pinpoint what is happening:
Are you growing from seed or nursery plants? If nursery plants, do they die shortly after being transplanted?
How were you watering them and does your flower bed have good drainage? Shasta is one flower that doesn't tolerate soggy roots. Barring that, I would review the following article on the care of shasta daisies to see if anything else might be amiss:
https://www.gardeningknowhow.com/ornamental/flowers/shasta-daisy/planting-shasta-daisies.htm