This is my favorite secret weapon. Diatomaceous earth (DE) is a powdery substance made from fossilized algae. To a woodlouse, it’s like walking through broken glass. It scratches their exoskeleton and dehydrates them.
Sprinkle a thin, dry layer of DE around plant bases, under pots, and at the edges of garden beds. But—and this is a big but—DE only works when it’s dry. Rain will turn it into mush. Reapply after a storm, and wear a mask when dusting; you don’t want to breathe in microscopic fossils.
