MULTIPLE USES: Cacti, bonsai, succulent containers, and potted plants SMALL 1/4-INCH SIZE - Lava rocks have an average size of approximately 1/4" in diameter 100% NATURAL - Pure volcanic rock with no additives, dyes, or fillers PROTECTS PLANT ROOTS - When placed at the bottom of the planter, lava rocks create a place for excess water to pool away from your plant's roots AIDS WITH WATERING - Lava rocks are naturally porous, they can absorb and slowly release excess water over time Midwest Hearth horticultural lava rocks are a great soil additive or topper for your plants, cacti, succulents and bonsai arrangements. They promote root health by allowing proper drainage of water from the plant roots. Small 1/4-inch average size is perfect for a variety of potted plants or flowers.