Don’t just stick to carving when decorating pumpkins. Use flat green spray paint to create a witchy pumpkin. Paint the pumpkin, then use a stencil kit (available at craft stores) to cut out the witch’s face.
Recycle the pumpkin stem as an appropriately gnarled witch nose.
Dress up the Green Witch with a witch hat and some braided yarn.
Line the inside of the pumpkin with sheets of colored gels in an appropriate color such as green. Use a battery-powered fluorescent light to illuminate the pumpkin.