What do you know about the mint family, the Lamiaceae, the sixth- or seventh-largest of the flowering plant families?
There’s a lot to admire about the family of plants that provides most of our common culinary herbs (e.g., basil, oregano, marjoram, rosemary, sage, thyme, summer and winter savories), many of our favorite tea herbs, and dozens (perhaps hundreds) of traditional medicinal herbs, not to mention many aromatics for use in flavorings, perfumes, and cosmetics.
You’ll also find some of them among our favorite landscaping plants. Think salvias, agastaches, and lavenders, bee-balms, hyssop, and Russian sage.
Many, if not most mint-family members contain strongly aromatic oils (think lavender, rosemary, basil, thyme, and sage), which account for their many uses as seasoning, flavoring, and perfuming agents.
Most of the mints that grow where I live in northern New England also have telltale square stems and delicate pinkish, lavender, or blue flowers. One outlier that’s become a favorite in my summer herb garden: the bright red bee-balm that seeds itself all over the place, makes a great cut flower and serves as a tasty tea to boot.
I grow most of the annual and perennial culinary species, plus bee-balm, lemon-balm, and hyssop in my garden (or, cold-sensitive species such as rosemary and lavender) in my greenhouse year ’round.
Out of curiosity, I started researching this plant family a couple of weeks ago because of the numbers of wild, invasive mint species that sprawl impressively, though uninvited, over my lawns and gardens. These perennials spread through underground stems (rhizomes) as well as seeds.
The spearmint (see photo), especially nasty, has woven an enormous network of tough, quarter-inch-thick rhizomes under an entire flower bed, spilling out into a large section of lawn, sending up a new plant every inch or two from the underground nodes. I’ve pulled up yards and yards and yards of the ropey invaders, but they still keep coming.
Wild catnip has invaded my biggest vegetable garden, seeding itself especially thick around the edges of the asparagus bed. We haven’t had cats for a couple of years to enjoy rolling around in the fresh leaves, though I’ve pulled many of the small plants to dry for winter tea. But the caztnip I've pulled and disposed of would make a cup or two of soothing nighttime tea for every resident of Merrimack County.
The ground-ivy comes up all over the lawn, but especially enjoys wandering into tilled soil. Once the snow melts and the spring rains come, it spreads rapidly into the vegetable garden beside our pond, turning into a thick mat sporting delicate purple flowers.
Although I find it annoying, it’s nowhere near as difficult to eradicate as spearmint. I’ve learned I can pull up a large mat of it using a spading fork stuck in at a shallow angle. During one of these digging exercises, I had an epiphany: What if I tilled up the poor, weedy soil around our septic system clean-outs and planted a few of these ground-ivy mats to grow as a ground cover in the unsightly spot? I plan to do just that right after our regularly scheduled septic-system maintenance this week.
One thing I’ve learned from my research is that most Lamiaceae have been used for centuries in traditional medicine. Many, perhaps most, are currently under investigation for potential uses in human and veterinary medicine, as insecticides or insect repellents, and as antifungal or antibacterial protection for crop plants.
Medicinal use of mints: use caution
These are potent plants, full of phytocompounds plants manufacture to protect themselves against harmful bacteria, viruses, and other assaults from the environments they evolved in.
If herbal medicine interests you, please approach the mints, especially their essential oils, tinctures, and concentrated extracts, with care. This goes for both over-the-counter and homemade remedies.
Although many have been used by traditional healers around the world for centuries, most herbs haven’t undergone rigorous testing for safety and efficacy, especially in pregnant/nursing women, children, elders, and people with chronic illnesses.
Seek out as much information as you can from books, online sources, and experienced herbalists in your area. Inform your healthcare practitioner whenever you begin using an herbal remedy.
Most herbalists recommend staying away from ingesting essential oils as medicines unless under the care and observation of a medical provider experienced with herbal medicines. Out of an abundance of caution, herbalists also urge pregnant and breastfeeding moms, as well as people with serious chronic diseases to avoid even using mint-family essential oils in massage oils.
Many mint-family species contain potent phytocompounds that affect the endocrine system, sometimes dramatically. For example, sage and peppermint, even as tea or food flavorings, can reduce the milk supply in breastfeeding women. The essential oil of pennyroyal, historically used to induce menstruation or as an abortifacient, can be lethal if ingested in a large enough dose to accomplish those purposes.
But there are many safe uses for mint-family herbs besides beautifying your gardens.
Tea What we usually call the “mints” (peppermint, spearmint, apple mint, etc., in the genus mentha, and catnip, in the genus nepeta) are traditional tea herbs. They’re beloved not only for their delicious taste and invigorating aromas, but also for easing queasy stomachs, calming anxiety, and promoting restful sleep.
Flavor cubes Freeze a few trays of strong mint tea, then use the ice cubes for cooling summer drinks.
Hair rinse Add one part strong mint (especially rosemary) tea to one part cider vinegar for a conditioning rinse you can either leave in or rinse out. The vinegary smell dissipates after drying.
Facial astringent Add a few finely minced leaves of fresh peppermint or other mint to a cup of witch hazel. Store in a glass jar for a week or more, shaking occasionally. Strain the herbs from the mixture after a week.
Mouthwash Chop a quarter cup of fresh mint, bee-balm, lemon balm, basil, thyme, or oregano leaves and infuse in a quart of boiling water. When cool, strain the herbs and store in the refrigerator.
Breath freshener Just chew on a few mint leaves. Sage teas and extracts have been used for centuries as a mouthwash for oral infections. Don’t use chew mint-family herbs if you’re breastfeeding, as even small amounts or sage and peppermint may reduce milk supply.
Scent up a space Use the essential oil of your favorite mint-family plant in a diffuser, or using a cotton ball, spread a few drops on a light bulb.
Moth repellent/scented sachet Tie a few branches of strongly scented mint (peppermint, sage, lavender, rosemary, bee-balm) together, or pull off a handful of leaves, and stuff them into the leg of an old nylon stocking. Suspend by a string inside a garment bag, tuck into bags of stored woolen clothing, or just place in your drawers to let your clothes soak up the scent. Refresh periodically to keep the scent fresh.
Dream pillows and nighttime face masks Lavender is such a well-known relaxant, many folks buy or make their own pillows or face masks to lull them to sleep. To make your own, crumble a few dried lavender flowers into the flax seed you’ll use for the pillow stuffing.
Lavender mist An easier way to use lavender to help you off to dreamland: Mix a few drops of lavender essential oil with a cup of vodka in a spray bottle. No, don’t drink it! Just mist your pillowcase, your sleep mask, or even your nightshirt lightly before turning in. It may take a bit of experimentation to get this whole thing right.
A final note: You’ll read in lots of places that peppermint-soaked cotton balls or bags of fresh peppermint leaves will repel rats. Take it from someone who’s done battle with these canny rodents for decades: the only way to keep rats away is to seek out and seal every tiny crack and hole that lets them into your buildings, then clean up and securely tuck away any signs or smells of food, including unwashed tin cans in the cellar recycling bins. Keep your pet foods, as well as your full garbage bags, in tightly sealed metal containers.
Margaret Boyles lives in a wood-heated house in central New Hampshire. She grows vegetables, eats weeds, keeps chickens, swims in a backyard pond in summer, snowshoes in the surrounding woods in winter, and commutes by bike whenever possible.