Margo Garden Products Gravel collection selects only high quality all-natural stone from regions surrounding the Southwest Pacific. Use landscape rock and gravel to control for water erosion, decoration around trees and flower beds, topcoat material for a ballast roof system and/or reduce water usage with a dry scape lawn and garden. Margo’s rock and gravel helps stimulate a healthy natural environment for fish in aquariums, ponds and reduces the amount of unhealthy debris in the water.