Kitty, it doesn't get that TALL, but if allowed to, it will arch out to make a plant that's in the neighborhood of 4-ft. across. I've never counted the petals. Sorry. But I suspect 40 may be pretty close to correct.
If deadheaded, I find it to be continuous-blooming, in my Coastal SoCal location. And it has excellent disease-resistance for me.
We have 3 of it, in differing locations, and all are excellent.
This image is from this morning, 6-9-22
Q