Powdery plant pot
I have a powdery, white residue on the outside of my terracotta pots of African violets? Should I clean it off? K. O’Rourke
This is caused by a build-up of calcium or fertiliser salts and can eventually kill the leaves that sit on the rim. Gently remove the plant and soil, then soak the pot in a 2:1 solution of water and vinegar for a couple of hours before scrubbing clean and replacing the plant.