Can This Strong-Scented Herb Really Keep Deer Away From Gardens?

Unlike their animated counterparts, real deer aren't welcome guests in most gardens as they're fond of munching on vegetables and flowers. While there are common ways to keep deer out of your yard, including fencing or using sprays, one commonly used strategy is growing plants they dislike. But plants classified as "deer-resistant," like many in the Lamiaceae (mint) family, aren't necessarily deer-proof or deer-repellent. Instead, it means that deer typically avoid these plants because they feature scents and flavors deer find unpleasant or too strong. Growing a combination of such plants is a good strategy to protect your garden, especially as they all vary in height, scent, and size. That said, no plant is foolproof.

One often-recommended option is Cuban oregano (Plectranthus amboinicus syn. Colues amboinicus), a soft, fuzzy herb in the mint family. Also known as Caribbean oregano, Indian borage, and Mexican mint, this hardy, aromatic perennial emits a heavy oregano smell when crushed; some blogs and nursery websites claim this scent can steer deer away. But is there any truth to the claim? While the plant has the right characteristics to be labeled as deer resistant, the evidence is thin and mixed, so homeowners should consider growing other options and not pin their hopes on Cuban oregano.

Rutgers University's New Jersey Agricultural Experiment Station ranks plants by deer resistance, assigning those in the Coleus genus (like Cuban oregano), the second-lowest grade on the scale: "Occasionally Severely Damaged." This means that deer will eat Coleus species and the damage may be significant. Other academic sources say that Cuban oregano is supposedly palatable to grazing animals, such as deer. This suggests that Cuban oregano may not be the deer-repelling cure-all for your yard. What's more, at a maximum height of just 18 inches, these plants wouldn't stop deer from walking through to get to a more appetizing treat in your garden. 

The best way to deter deer from destroying your garden is to choose plants whose resistance to grazing animals is backed by scholarly research, as part of a broader deterrence strategy. Such options include rosemary (Salvia rosmarinus) and members of the Origanum (oregano) genus. You can also try fragrant catmint (Nepeta), garden sage (Salvia officinalis), and Lemon balm (Melissa officinalis), all of which feature powerful scents when crushed. Meanwhile, common milkweed (Asclepias syriaca) bears a sticky sap deers avoid and has the added bonus of being a core food source for Monarch butterflies. Keep in mind, though, that if they're hungry enough, deer will eat any plants, no matter how strong their flavor is. This is why plants can't be a core strategy to keep these animals away — only a part of it.