The Ghost Cactus isn't actually a cactus. It's a Euphorbia (Euphorbia lactea) and it is white because it lacks chlorophyll. We classify this as a rare plant because they aren't available Starting Vegetable Seeds Indoors in March Zone 5B Huge Monstera Up the Wall and No Moss Pole, Yes you read it Right!! Pineapple Plant Indoor Care Guide Proven Tips from a Pro Plectranthus 'Purple Swedish Ivy' Forget Me Not Nursery Indian, Alaska