I'm going to be getting chickens soon, and need to replan my herb garden to accommodate them. What herbs are good for chickens? Do I need to be careful where I plant them, so they don't get overharvested? Are there any I should avoid?
Chickens can eat almost any cooking herb that you'd commonly plant in your garden, but some are more beneficial to the chickens than others. Here are some with noted health benefits:

• Mint: Mint's powerful smell can help combat any undesirable coup fumes and also keep insects at bay. In addition, it can encourage new feather growth in chickens and has been said to have a calming effect. (Calmer hens equals more eggs!) It can even be served fresh, frozen, or dried, and obviously has many household uses, as well. Because mint is a prolific grower, it's safe to plant near the coup. If it spreads inside, the chickens can trim the excess without harming the overall supply.

• Lavender: Lavender is calming for chickens and humans alike! In addition, it has a lovely smell that mixes well with mint and other herbs. This smell helps dispel pests. Lavender is also good for the circulatory system, increasing blood flow when hens might not be moving around as much (during winter, cold snaps, or when sitting on eggs.) The seed-shaped flowers of lavender are also enjoyable for chickens to forage, providing some mental exercise.

• Oregano: Oregano's smell deters pests and mixes wonderfully with the basil and tomatoes in your garden (which chickens also love!) Oregano grows best when harvested often, so whole springs can be hung in your coup for the chickens to pick at and scavenge. It's a natural antibiotic that's full of vitamins and antioxidants. You can even add dried oregano into your feed for these benefits, although it won't be as potent as fresh sprigs. 

• Thyme: Thyme, like the others, is aromatic and mixes wonderfully with the smell of lavender. (Just check your soap scents!) Like oregano, thyme is a natural antibiotic that also aids in respiratory stability. Thyme spreads, like mint, so it's safe to plant near the coup and let the chickens control the excess. It can be hung in full sprigs like oregano or dried. 

Additionally, any of these herbs can be soaked in vinegar and used as an all-natural pest control due to their aromatics. Plant extra!