You can also have houseplant fun with fruits, nuts, herbs, and spices. From the common carrot to the exotic cherimoya, dozens of foods have pits, seeds, and roots waiting to be rescued from the compost bin and brought back to life on your windowsill. Planted and nurtured, the shiny pomegranate seeds left over from breakfast and the piece of neglected gingerroot in your refrigerator will grow into healthy, vigorous houseplants--kitchen experiments in the wonder of botany.