Hmm.. I'd be careful letting them eat house plants, there are many kinds of plants that can be toxic to dogs. Here's a list of some common ones: http://www.aspca.org/pet-care/poison-control/plants/?plant_toxicity=toxic-to-dogs If your not sure what kind of plants you have or just don't want him eating them in general, you might want to buy some Bitter Apple spray or Hot Pepper spray.. They both taste terrible (though the pepper has a bit more bite to it) and will deter your dog from ever tasting the house plants again.