Last year I purchased an ornamental sweet potato vine from a local store. The leaves of the vine were a beautiful silvery and lavender/purple shade. At the end of the season, while pulling the vine up from the planter, I discovered a sweet potato, which I saved and have sprouted on my kitchen windowsill. I have pinched off the tips of the vines, rooted and planted slips from this sweet potato in containers all over my yard. My question is this: Why are my plants not the lovely silvery lavender/purple colored leaves that the parent plant was last year?
