Your hosta leaf is absolutely very well done. I hope you post your AFTER photo, too.
I'm late to this posting, but I can offer up an idea that you might not have thought of. Being an artist myself, I'd be concerned about paint peeling off in time. For that reason, I'm probably not a good one to make any suggestions. For my two cents, I'd suggest concrete stain. Permanent, fast, and easy. I found a website for a homemade concrete stain which I used to stain rocks in my yard to retain beds. In our droughts, this seemed to be the most color my developing yard has seen. Maybe in a couple more years, it will look better. However, point being is that it is the easiest thing I've ever done. It sure was nice to change the gray rocks.
I have no doubt, Deb, that yours turned out better than mine. I do hope you keep this thread going by posting your 'after' photo. I'm eager to see it... and hear your thoughts on using stain vs paint.