Answer: A cat repellent can be applied to your houseplants. These repellents will need to be applied every few weeks to stay effective. You could also cover the exposed potting soil with rough decorative rocks to discourage cats from digging. Or you can arrange flat rock pieces on the surface that are too heavy for the kitten to move. We doubt pine cones would harm your kitten, but you can check with your veterinarian who also may have ideas for protecting your houseplants.