Can I let my dog chew on a few fresh mint leaves from my herb garden?

A couple of fresh mint leaves are usually harmless for most dogs, but it should be done with caution. The concern is that concentrated mint oils or consuming a larger quantity of leaves can lead to stomach irritation, resulting in vomiting or diarrhea. If your dog tries a leaf or two, watch them for the next several hours for any digestive upset. It's safer to avoid letting them make a habit of it, and if you notice any concerning symptoms, a call to your vet is a good idea.