I was looking at “gravel” at Home Depot, some Mexican gray pebbles?? I think they would look nice. And yes I’ve read they can be helpful in that regard. You sure do have some beautiful plants, most of those are succulents correct?? Beautiful collection either way. I have a very large balcony and have a bunch of different kinds of marigolds out there. I used to plant honeysuckles. But between the squirrels eating them and watching praying mantis’s attack the hummingbirds they attracted. I went with the marigolds.