Your new fountain garden looks lovely! I  suggest you  sprinkle the Osmocote Plus into the bare soil around the plants now before they spread out and make it more difficult to get the product near the root zone. Osmocote will feed slowly all summer long and release more nutrients as the weather heats up and the plants grow faster and need more fertilizer. Just follow the amount recommended on the package and work the granules into the top two to three inches of soil and you are done for the season. Hope you take another image in mid summer to show us how your garden has grown. Keep growing, Marianne Binetti