With their unusually striped or mottled leaves, variegated plants add interest and intrigue in the garden. The variegation is due to a lack of the green pigment chlorophyll in some of the leaf cells, which is often the result of a random cell mutation. Sometimes variegated plants revert to their original leaf, producing stems bearing green foliage. The green leaves photosynthesise more efficiently than variegated ones, so they grow more vigorously. If you don’t cut them out they will dominate, and you will lose the decorative value of the variegation. Check your plants, and if you see any examples of this, follow the stems right down to their base where they meet the branch and cut them off.