Heal All (Prunella vulgaris)
Self Heal, Common Self-Heal, All-Heal, Heart of the Earth, Prunella, Brunella, Woundwort, Wound Root, Slough Heal, Blue Curls, Dragonhead, Hercules’ Woundwort, Hook-Heal, Heart of the Earth, Carpenter’s Herb, Xia Ku Cao, Lawn Prunella
About This Plant
This unassuming little plant with a lofty name, Heal All, is one of the most widely distributed plants in the world. It grows about a foot tall and creeps along the ground like others in its Mint family, growing about 18-24 inches wide. It often shows up in lawns and when mowed repeatedly forms deeply matted, depressed colonies. Heal All is a herbaceous perennial that is hardy in USDA zones 5-9.
Heal All’s leaves are slender and vary in shape, from broadly lanceolate to ovate, each about one inch long and a half-inch wide. The leaf margins can be smooth or have scattered blunt teeth and the leaves have a reddish tip. Each leaf has three to seven veins going from the middle vein to the margin. The leaf stalks are generally short but can be up to two inches long. There are several small and densely arranged leaves below and throughout its flower cluster. Heal All’s stems are square in profile and usually have long white hair on them. The flowers form somewhat square, club-like clusters at the terminal ends of the flower spikes. Just below this cluster is a pair of stalkless leaves that stand out on either side like a collar. Individual flowers are about the size of honey bees and come in shades of purple and white. Heal All can bloom anywhere from about April to the first frost, lasting about two months once it starts. The flower stalks begin blooming at the base of the cluster and advance toward the top. Honey bees, bumblebees, and some kinds of butterflies are attracted to their nectar. The generally white flowers are tubular in shape with a purple “hood”. Their upper lip is three-tipped while the lower lip is larger, showier, and two-lipped. Heal All mostly grows in the Winter and Spring and moves into dormancy after the seeds form in summer. Each flower produces four tiny seeds. Heal All spreads out from a central taproot that sends stalks across the ground in a star shape, attaching new roots to the ground as it goes.
Heal All can be found growing in moist to mesic black soil prairies, along rivers and lakes, meadows, thickets, woodland borders, pastures, abandoned fields, and in yards. It can be a good choice for ground cover, along roads, or in naturalized settings such as meadows and prairies. It also can be used for spilling over walls or even in containers if you wish to contain it. It is deer, rabbit, and pest resistant. Heal All was introduced to many countries in the 1800s and has become invasive in the Pacific Islands including Hawaii, Australia, and New Zealand. There are two subspecies to Heal All, or Prunella vulgaris – subsp. lanceolata and subsp. vulgaris which is native to Europe.
Heal All seeds can be sown directly any time of year. They can even be sown into lawns. Sow the seeds sparingly as they will choke out other seedlings. Ideally, the areas are scratched first with a rake and once seeds are sown, scratched again to lightly cover them with soil. Six to eight weeks after sowing, the Heal All seedlings can be easily distinguished from other nearby weed seedlings. Seeds can also be sown in very early Spring in a flat outdoors. The seeds will actually benefit from a period of moist cold before germinating. Plants can also be easily propagated by root segments that can be removed from clumps.
Heal All should be spaced about 12” apart.
Heal All is relatively easy to establish and requires little care. It thrives in loamy soil with high organic content. The plant is quite adaptable however and will do fine in average soil as long as it is well-draining. It especially prefers damp soils but is somewhat drought tolerant once established. It tolerates full sun to partial shade. It is well suited for partially shaded moist sites at the front of a perennial border or in a woodland garden where it can happily spread to form a small colony. Deadheading the plant will help to extend the flowering season.
For medicinal purposes and maximum potency, the aerial parts of the plant should be harvested during the mature flowering stage, typically from June to September. If you cut the aerial portions and leave the root system intact, it’s possible to have two flowering periods in a growing season.
The seeds are mature once the flower heads turn brown and dry. Simply pluck the flowerheads off the stems and garble them well in the palm of your hand. You’ll see the seeds separate into your hand. You can either pick them out or put the plant material into a fine mesh sifter placed over a bowl and shake it vigorously. The tiny seeds will fall through the mesh and can be collected from the bowl. Or, you can gather the dried flowerheads, garble them in your palm and simply toss the material where you hope to see Heal All grow.
- Naturalized gardens and meadows
Heal All is edible, though not especially popular in cooking. It has a subtle, bitter taste. Some say it has the flavor of bland Romain Lettuce. Others say it tastes a bit like Rosemary. Heal All is indeed very high in rosmarinic acid, one of the well-studied antioxidants that is found in Rosemary. It is suitable as a potherb or the leaves can be tossed into a salad, soup, or stew. The plant is good for you with many, gentle, medicinal properties, so wherever you can find a place for it in your kitchen, go for it.
So this plant, whose popularity has waned in recent years with herbalists, is actually being studied quite extensively by researchers for a number of significant attributes. There is promising research on its action as an antiviral in relation to herpes and AIDS as well as research on its antibacterial action, inhibiting the growth of pseudomonas, Bacillus typhi, E. coli, and Mycobacterium tuberculi, as well as research into its effects on diabetes and cancer. It is also an anti-inflammatory, astringent, and antioxidant. It has long been known as a panacea of herbs, helpful for many different maladies, yet with no known safety issues or contraindications for use. Heal All contains polysaccharides (like many mushrooms do) which are known to be immunomodulating or balancing for the immune system, which means it can have a positive effect on seasonal allergies and chronic inflammation. It has been used on all types of wounds, both inside the body and outside, for headaches, eye complaints, ulcers, skin irritations, hemorrhoids, menstrual problems, and more. It is said the blossoms have the same shape as a mouth and throat which under the Doctrine of Signatures would indicate the plant is good for healing ailments of the mouth and throat, for which has always been a popular use for it. It can be made into a tea that is slightly bitter or extracted into alcohol or infused into oil.
Prunella vulgaris, or Heal All, is thought to be native to Eurasia but was also widely distributed in North America prior to European exploration. Some attribute this discrepancy to the continents each having their own subspecies of the plant.