Good clarity, colors and lighting. I think it might be a little stronger if the curve of the wall lead to a bench, or a particularly colorful group of flowers, or perhaps a person. But we can't always put these things where we want them :-) Good angle on the curve, it definitely causes the eye to travel across the photo.
I'm not sure but should the line obscure the subject...or should they just lead too the subject....I'm thinking it is the latter. A better shot for the challenge might hav been to have picked one of the sections and shot the garden through it there by seeing more of the subject and less of all the lines It might have been more of a framing challenge shot but I think enough of the lines included about the circle would have got you by.. I can see your attraction to all the shadows but they really don't lead any where to me.
lots of lines here. unfortunately those center columns seem to block the movement you're trying to create. i wish you had found a nice focal point, perhaps some flowers and found a line leading to them...perhaps some of the shadows created by these lines would have done the trick.