Tea Time: Self-heal

Prunella vulgaris can be found all over the place. It has also been used to treat just about everything. What else would you expect from a plant known commonly as self-heal, heal-all, all-heal, and woundwort? The medicinal value of this plant has been appreciated for centuries across its expansive range, and studies evaluating its medicinal use continue today. Being such a ubiquitous species – both as a garden plant and a native plant (and also a common weed) – and because it has so much clout in the world of herbal medicine, it’s an obvious candidate for Tea Time.

Self-heal is a member of the mint family (Lamiaceae), easily distinguished by its square stems, opposite leaves, and bilabiate and bilaterally symmetrical (or zygomorphic) flowers. One surprise is that, unlike the many aromatic members of this family, the foliage of self-heal lacks a strong scent. P. vulgaris occurs naturally across Asia, throughout Europe, and in parts of northern Africa. It is also widely distributed across North America. Apart from that, it has been introduced to many regions in the southern hemisphere and has also been frequently moved around throughout its native range. Eurasian varieties now intermingle with North American varieties, which can make it difficult to determine a native individual from an introduced one.

self-heal (Prunella vulgaris)

Self-heal is an adaptable plant that tends to prefer shady, moist locations, but can also be found in open, dry, sunny sites. Find it along forest edges, roadsides, ditches, and trails, as well as on the banks of streams, lakes, and reservoirs. It occurs in gardens, both intentionally planted and as a weed, and can escape into lawns, vacant lots, and open fields, as well as into nearby natural areas.

P. vulgaris is an evergreen that grows both prostrate and upright, sometimes reaching 1 foot tall or more (but is often much shorter). It has shallow, fibrous roots, and its stems root adventitiously as they sprawl across the ground, frequently forming an extensive mat or groundcover. Its leaves are oval to lance-shaped and measure about one inch long. Lower leaves have petioles, while upper leaves may become stalkless. Leaf margins are entire or can be slightly toothed. As plants age, they can develop a coppery or purple-bronze color.

the leaves of self-heal

The flowers of self-heal are generally a shade of purple, but can also be white, pink, or blue. They bloom irregularly in a spike measuring up to two inches long. Flower spikes are thick, dense, cylindrical, and made up of whorls of sharp-pointed bracts. Flowers bloom irregularly along the spike and occur from late spring/early summer into the fall. Each flower produces four nutlets, which sit within a cup-shaped, purple calyx.

As a medicinal herb, self-heal has been used both internally and externally to treat a long list of ailments. These include sore throats, diarrhea, fevers, intestinal infections, liver problems, migraines, heart issues, dermatitis, goiter, and thyroid disfunction, just to name a few. It has been used topically to treat skin irritations, bites, stings, and minor cuts and scrapes. This is thanks to its antimicrobial properties and its ability to stop bleeding. A report in the journal Pharmaceuticals (2023) calls P. vulgaris an “important medicinal plant” due to its “rich chemical composition” and its “pharmacological action.” Chemical analyses find the plant to be a valuable source of phenolic compounds, flavonoids, rosmarinic acid, and ursolic acid, among numerous other compounds. If you are curious to learn more detailed information regarding this plant’s medicinal value, you can refer to the above report, as well as one found in Frontiers in Pharmacology (2022).

self-heal tea

P. vulgaris is an edible plant, and its young leaves can be eaten raw or cooked. The leaves together with the flowers can also be dried and used to make a tea. This is how I had it. I used about two teaspoons of dried leaves to one cup of water. Feel free to use more if you would like. I thought the tea was pretty mild. It had a slight sweetness to it and a hint of mint flavor. It has been described as bitter, but I didn’t find it to be overly so (although I may have a higher tolerance for bitterness). Sierra tried it and said that it tasted like “water left over from something else.” That might be because it was more diluted than she would have preferred. Overall, I thought it was a pleasant experience and would be happy to drink it again.

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Tea Time: Kentucky Coffeetree

Learning to identify Kentucky coffeetree in the winter brings you one step closer to making a coffee-like (albeit caffeine-free) beverage from its seeds. Humans have a long history of occasionally using the “beans” of Gymnocladus dioicus to make this tisane, which explains common names like coffeetree, American coffee berry, and coffeenut. The process is a bit time consuming, and the end result is mixed, but foraging adventures like this are all about the experience. This drink is not likely to replace whatever you are currently drinking in the morning, but it does offer an interesting diversion.

fruit of Kentucky coffeetree (Gymnocladus dioicus)

Winter is the best time to collect the pods, which are flat, leathery, brown to black in color, and about 2 inches wide and 6 inches long. The stocky fruits are often found hanging from the tips of the tree’s bare branches. Many also fall to the ground over the course of the season, making them easier to collect. If you split the pods open early in the season, you’ll find the seeds embedded in a sticky, neon green goo that will stick to your hands and clothes. As the year progresses, the glue-like substance dries out and is easier to deal with. The seeds are dark, extremely hard, rounded and flattened, and about the size of a penny or nickel. The funiculus, which is a short stalk that connects the ovule/seed to the ovary, tends to be fairly prominent and something you don’t often get to see on seeds.

inside the fruit of a Kentucky coffeetree

Once you’ve collected several pods and removed the seeds from the gooey innards, soak the seeds for an hour or two and then rinse them, making sure to remove dried up goo and any remaining funiculi. Pat the seeds dry and place them in a baking dish with a lid for roasting. The roasting process is said to eliminate the toxicity of the seeds. The lid is important because several of the seeds will pop open during roasting and will fly around in your oven if they aren’t contained.

The fruits of Kentucky coffeetree contain a toxic compound called cytisine, an alkaloid that is similar in action to nicotine. The Handbook of Poisonous and Injurious Plants by Nelson, et al. states that “the cytisine content of the seeds is quite low; and chewing one or two would not be expected to produce toxic effects.” Actually, the bigger risk of chewing one of these rock hard seeds is breaking your teeth. Cytisine poisoning includes typical symptoms like diarrhea and vomiting; in extreme cases it can lead to coma and death. If the seeds are properly roasted, you won’t have to worry about any of this, but as with anything you are trying for the first time, start with small amounts.

seeds of Kentucky coffeetree

Times and temperatures for roasting vary depending on who you’re getting your information from. I went with 300° F for 3 hours (which ended up being 3 and a half hours because I forgot to take them out in time). One source suggested roasting the seeds for only 2 hours for better flavor, but I decided to err on the side of caution and roast them for longer. Many of the seeds will have popped open during the roasting process. For those that haven’t you will need to use a nutcracker or some other comparable tool to crack the seed coat and remove the insides. Dispose of the seed coats and grind the remaining bits into a fine powder using either a coffee grinder or mortar and pestle. You’ll end up with a fine, chocolate-colored powder which you will use to make your “coffee.”

You can prepare this beverage in the same way you would typically choose to make coffee, but keep in mind that upon adding water, the fine grounds quickly turn to a mud-like substance and will block up the filter you are using. For this reason, I recommend small batches. I found Kentucky coffeetree “coffee” to be very earthy and rich and somewhat similar to strong black coffee. Sierra tried it and immediately exclaimed, “That’s nice!” and then proceeded to give it two thumbs up. Some people like black coffee. I added cream to it and found it much more pleasant to drink. Other people don’t think this beverage tastes like coffee at all and instead call it tea-like, chocolaty, fruity, or “akin to mud,” among other more negative reviews. I think it’s a drink that could grow on me, but considering the effort it takes to make one cup, I don’t see that happening any time soon.

Kentucky coffeetree “coffee grounds”

Have you tried making “coffee” from the seeds of Kentucky coffeetree? Let us know what you think about it in the comment section below.

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Tea Time: Linden Flower Tea

Lindens make great trees for urban areas. A few species and hybrids in particular are commonly planted in parks, yards, and along the streets of cities across the northern hemisphere and have been for decades – centuries even. They cast dense shade, are tolerant of a variety of climates and soil conditions, and are generally easy to maintain. For much of the year as you move throughout the city you live in, you likely pass by dozens of lindens without thinking twice about them. They are ubiquitous, conventional, ordinary, common. Unless they’re in bloom. For a few weeks in early to mid-summer, flowering lindens produce an impossibly sweet fragrance that can’t be ignored. Along with the scent comes the sound of hundreds of buzzing bees collecting pollen and nectar from the pendulous blooms.

Lindens are trees and shrubs in the family Malvaceae and genus Tilia. Around 30 or so species are found in temperate regions across the northern hemisphere, mostly in Europe and Asia. Depending on who you ask, there are between one and three species native to North America. Tilia caroliniana and Tilia heterophylla are considered by some to be varieties of Tilia americana, or American basswood, which is distributed across central and eastern United States and north into parts of Canada. Another common name for linden is lime because words used to refer to the tree in older languages were similar to the word lime. The name basswood comes from the tree’s fibrous inner bark, known as bast.

Linden leaves are generally heart-shaped and asymmetrical with serrate margins. Small clusters of little yellow to white flowers form at the end of a slender stem attached to a narrow, ribbon-like, yellow-green bract. The bract aids in seed dispersal by helping the fruits float on the wind away from the parent tree in a manner similar to the samaras of maple trees. The fruits are small, round, hardened drupes that resemble little peas. The fragrant, nectar-rich flowers are not only favored by beekeepers for honey production, but also have a long history of being harvested for making tea (i.e. tisane). Linden flower tea is said to have a number of medicinal uses and health benefits, all of which I take with a grain of salt. This series of posts isn’t meant to be an investigation into the health claims of plants, but instead an opportunity for me – out of sheer curiosity – to try making tea out of a variety of different plants . If medicinal uses interest you, I encourage you to seek out credible, peer-reviewed sources.

I made linden flower tea from flowers I collected from Tilia cordata, commonly known as littleleaf linden. It was an easy one to find due to its popularity as an urban tree. The natural distribution of littleleaf linden extends from Britain across Europe and into western Asia. Its triangular-ovate shaped leaves are 4-10 centimeters long, glossy green on top, and pale green on the bottom with tufts of orange hairs along the leaf veins, concentrated at the base of the leaf where the leaf blade meets the petiole. The tree can reach up to 21 meters tall and has an oval or rounded-pyramidal shape, though many trees in urban areas are cultivars and can be smaller and more compact.

I harvested the flowers – bracts and all – in late June. It’s advised that they not be harvested directly after a rain (or after being hit by sprinklers), and that they are harvested when the flowers are newly opened. I presume this is because the flowers are at their freshest at this point and will be the best for making tea. I layed the flowers out to dry on a clean kitchen towel on top of a metal cake rack. It only takes 2 or 3 days for them to dry. After drying I removed and saved all the flowers and threw out the bracts and stems, but apparently you can use the entire inflorescence if you’d like.

There are several linden flower tea recipes online. I went with 3 cups of boiling water poured over 1 tablespoon dried linden flowers, covered and steeped for 15 minutes. The resulting tea was an appealing pastel yellow color. I tried it plain as well as sweetened with a little bit of honey. I preferred it sweetened, but unsweetened wasn’t too bad, just a little bitter. It has a floral taste and pleasant smell. Sierra said it tasted earthy, like something she wasn’t supposed to be drinking. Despite that odd review, she said she liked it. Since several sources discussed the calming, sleep-inducing effects of the tea, I made sure to drink it in the evening when it would be normal for me to be feeling sleepy. I suggest you do the same.

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