4" Arizona Snowcap CactusArizona Snowcap Cactus (Mammillaria gracilis Arizona Snowcap) Arizona Snowcap Cactus is a charming miniature cactus known for its dense covering of tiny white spines that give the plant a soft, snowy appearance. The small, rounded stems cluster tightly together over time, forming attractive mounds that look almost dusted with fresh snow. Its compact size and delicate texture make it a favorite for windowsills, dish gardens, and cactus collections.