herbs – Steven Foster's Herbalblog

Passionflower – Herb n’ Food

Native to Argentina, Brazil and Paraguay, Passiflora caerulea, is one of three semi-hardy species of passionflowers, and is widely cultivated as a window box plant or gardens in southern Europe, surviving temperatures of -15°C. It was cultivated in France as early as 1625, and first document in London in 1629. Today it is one of the most widely-grown passionflowers in horticulture, and source of many hybrids. These photos were taken in a garden in Podgorica, Montenegro.

Passionflower; Passion flower; Maypop; Purple Passionflower; Passiflora incarnata — Passionflower, Passiflora incarnata

Intent on reaching the swimming hole on a seething July afternoon, my attention was diverted by a loud pop under foot. Relieved by the realization that the object was vegetable rather than animal, the victim plant caught my attention again, this time by the indescribable, intricate beauty of its bloom. I had stepped on a fruit of the passionflower or maypop. Such is the memory of a New England transplant upon first encountering a maypop in the Ozarks. This fast-growing perennial vine is more widely known as passionflower (Passiflora incarnata). In the Southeast it’s also called apricot vine.

Passionflower’s Name

What design of nature or serendipitous evolutionary event could create a flower of such unusual beauty? Such radiance is beyond scientific rationale. Best to describe it in religious terms. The first Europeans to observe the plant did just that. The name is derived from flos passionis, a translation of fior della passione, a popular Italian name which was applied to the plant to signify religious symbolism. The floral structure was seen to symbolize the implements of the crucifixion—the Passion of Christ— his period of suffering following the Last Supper and the Crucifixion. The three spreading styles atop the stigma were thought to represent the three nails by which Christ was attached to the cross. The five hammer-like anthers atop of the stamens exemplify the hammers used to drive the nails, or to others, Christ’s five wounds. Beneath these floral structures is a fringe of colored filaments, known as the corona. It was believed to depict a halo or perhaps the crown of thorns. Beneath it sits the corolla—with ten petals, each representing the ten apostles at the Crucifixion— save Peter and Judas. Some early missionaries envisioned that the bell-shaped, unopened or recently closed flower held these sacred symbols from the view of heathens who had not yet been converted to Christianity. If that’s not enough, the lobed leaves and long green vines further represent the hands and whips of Christ’s prosecutors. And so, both the common and Latin names—passionflower (Passiflora)—speak of these mysteries. Thomas Johnson editor of the 1633 edition of Gerarde’s Herball described these notions for what they were: “The Spanish Friers for some imaginarie resemblances in the floure, first called it Flos Passionis, The Passion floure, and in a counterfeit figure, by adding what was wanting, they made it as it were an Epitome of our Saviors passion. Thus superstitious persons semper sibi somnia fingunt” [always see contrived images]. The species name of passionflower “incarnata” means “made of flesh or flesh-colored.” Maypop, of course, refers to the fruits, the shape and size of a hen’s egg, which open with a resounding pop when squeezed.

Passiflora incarnata, Passionflower, or Maypop. Passionflower is variously wildflower, weed, ornamental perennial, delectable edible, or medicinal herb. The fruits, "maypops", are edible. The whole above ground plant is considered a mild nerve sedative and a sleep aid. When tension, restlessness and irritability result in difficulty in falling asleep, passionflower is an herbal remedy of choice. — *Passiflora incarnat*a, Passionflower, or Maypop. Passionflower is variously wildflower, weed, ornamental perennial, delectable edible, or medicinal herb. The fruits, “maypops”, are edible. The whole above ground plant is considered a mild nerve sedative and a sleep aid. When tension, restlessness and irritability result in difficulty in falling asleep, passionflower is an herbal remedy of choice.

Passionflower Diversity

Depending upon your perspective passionflower is wildflower, weed, ornamental perennial, delectable edible, or medicinal herb. The flowers of one hybrid P. x alatocaerulea (a cultivated hybrid between P. alata and P. caerulea) are used in perfumery. That covers all the bases of the definition of an herb— any plant or plant part used for culinary, fragrant or medicinal purposes. Therefore, it deserves a place in herb gardens. Here we will primarily focus on the common maypop, wild passionflower, or apricot vine (P. incarnata) the only native species that is hardy and can be widely cultivated in much of the U.S.

Yellow Passionflower, Passiflora lutea, a member of the Passifloraceae or passionflower family, a predominantly Neotropical American plant group of over 400 species, with three temperate North American representatives including, Passiflora lutea one of the most diminutive of all passionflowers, with blooms barely reaching 2cm in diameter, and fruits the size of a pea. It occurs from Pennsylvania to Florida, west to Texas, northward to Illinois. Although yellow wild passionflower is very rarely mentioned in the medicinal plant literature, in 1840 Dr. L. Phares of Mississippi is said to have used this small North American vine interchangeably with the common passionflower. I have made a tincture (alcohol extract) of both plants. They have a very similar flavor and fragrance. The fruits are decidedly different, though. Those of P. lutea are globular black berries, about 1/4 inch across. They have a much more acidic flavor than maypop. — Yellow Passionflower, *Passiflora lutea* one of the most diminutive of all passionflowers, with blooms barely reaching 2cm in diameter. It occurs from Pennsylvania to Florida, west to Texas, northward to Illinois.

The passionflower (P. incarnata) is an herbaceous perennial, trailing or climbing, with tendrils. The white to blue purple flowers are up to three inches across. It occurs in waste ground, along fence rows, roadsides, and fields from Pennsylvania to southern Florida, west to east Texas and north to southern Missouri, and Ohio. In the United States we have about 25 native or naturalized species of Passiflora, but only the passionflower and its diminutive relative wild yellow passionflower (P. lutea), with tiny yellow flowers about an inch across, are hardy natives. Wild yellow passionflower is rarely grown in gardens.

The genus Passiflora, with only a handful of temperate species, explodes in diversity in the American tropics with about 500 species. An additional 20 species occur in Indomalaysia and the south Pacific islands. Some have edible fruits. Others do not. About 30 species of passionflower have edible fruits. At least 40 species and numerous cultivated varieties are found in American gardens, primarily in warmer areas.

Passiflora edulis, passion fruit, passionfruit is used as a commercial source of passionfruit beverages in the tropics. Since the fruits have poor keeping qualities they are seldom seen outside of local tropical markets. A folk remedy for insomnia, neuralgia, muscle spams and epilepsy. Juice considered a digestive aid. — *Passiflora edulis*, passion fruit, passionfruit is used as a commercial source of passionfruit beverages in the tropics. Since the fruits have poor keeping qualities they are seldom seen outside of local tropical markets. A folk remedy for insomnia, neuralgia, muscle spasms and epilepsy. Juice considered a digestive aid.

The undisputed edible king of passionflowers is passionfruit or purple granadilla (Passiflora edulis) which is cultivated for its edible fruits and juice. It is native to southern Brazil, Paraguay and northern Argentina. A large passionfruit industry in Brazil grows purple-fruited forms for the fruits, while yellow-fruited cultivated forms are used for juice extraction. Passionfruit is grown commercially in Australia, New Zealand, Hawaii and other tropical regions. It was introduced into Hawaii in the 1880s, where it became a popular home garden flower and fruit on the islands. By the 1930s it had become wild on every island in the archipelago. Commercial cultivation operations are also found in Kenya, South Africa, India, Pacific islands, and other tropical regions where it thrives. According to Arthur O. Tucker passionfruit has proven hardy in protected situations as far north as Ontario. If you do buy seeds or plants of this species and don’t live in a subtropical area, you will probably want to bring it indoors for the winter. The vast majority of scientific references to Passiflora species refer to the passionfruit and its many cultivars and hybrids. Much of the research has focused on attempting to unlock the unusually complex, sweet, delicate-perfume flavor of the fruits.

Other passionflowers are grown as subtropical food plants as well. The tropical American species running pop (P. foetida), now a weed in the old world tropics, is grown for its fruit, as is the banana passionfruit (P. mollissima). Yellow granadilla, or water lemon (P. laurifolia), also known as Jamaica honeysuckle, is a commercial fruit crop. Its name does not derive from any resemblance to honeysuckle (Lonicera species) but from the fact that the fruits are eaten by sucking out the pulp from the rose-scented fruit. Sweet calabash (P. maliformis) is grown to produce grape-flavored juice. Giant granadilla (P. quadrangularis) sports a large fruit about eight inches long which is eaten as a vegetable. Individual fruits of cultivated varieties of giant granadilla may weigh as much as several pounds. When still green the rind is boiled and eaten as a vegetable. If ripe, it is eaten iced (with sugar) or the fruit-wall may be candied. Members of the genus Passiflora hybridize readily and have produced numerous cultivated hybrids, primarily grown in the tropics for fruit production.

Passiflora vitifolia, Grapeleaved Passionflower, Crimson Passionflower is a showy native to Central America. The berry-like fruit is sour, then slowly ripens over a month a flavor likened to sour strawberries.

Other passionflowers such as red-flowered species P. vitifolia which sports crimson red flowers, or blue passionflower (P. caerulea) are grown as ornamentals. They do not produce edible fruits. Some cultivars of the blue passionflower such as ‘Constance Elliot’ which sports white flowers, are reported to be hardy in protected situations as far north as central Delaware. The tender ornamental passionflowers can be grown as annuals, taking cuttings in late summer rooting them before the first frost, or growing them in a large container to winter it over.

Native to Argentina, Brazil and Paraguay, Passiflora caerulea, is one of three semi-hardy species of passionflowers, and is widely cultivated as a window box plant or gardens in southern Europe, surviving temperatures of -15°C. It was cultivated in France as early as 1625, and first document in London in 1629. Today it is one of the most widely-grown passionflowers in horticulture, and source of many hybrids. These photos were taken in a garden in Podgorica, Montenegro. — Native to Argentina, Brazil and Paraguay, Passiflora caerulea, is one of three semi-hardy species of passionflowers, and is widely cultivated as a window box plant or gardens in southern Europe, surviving temperatures of -15°C. It was cultivated in France as early as 1625, and first documented in London in 1629. Today it is one of the most widely-grown passionflowers in horticulture, and source of many hybrids. These photos were taken in a garden in Podgorica, Montenegro.

Growing Passionflower

Subtropical edible or ornamental passionflowers are primarily relegated to the realm of the specialized collector, or those who have access to a greenhouse. But the passionflower (P. incarnata) can be grown by most herb gardeners. While passionflower is commonly regarded as a southern plant, it will grow as far north as the Boston area, and I suspect, if placed in a well-protected situation and mulched through the winter, it would even survive as a perennial in central Maine. Here in the Arkansas and Missouri Ozarks, the native passionflower withstands temperatures of -25° F. without any protection. When purchasing seeds or plants it’s probably a good idea to at least inquire where the plant material originated, if the seller knows. Passionflower seeds or plants from south Florida are probably likely to survive in New England, than plants originating from more northerly areas. While dying back to the ground each year, it makes a marvelous fast-growing climbing cover for a fence, or can be trained on a trellis as a focal point for the herb garden. In the South it will grow 20—30 ft. in a single season. In more northerly areas, expect a growth of about 15 feet in a season. Passionflower grows in waste places, thriving in relatively poor, sandy, acidic soils. Good drainage is essential. Full sun is necessary.

Passiflora incarnata, Passionflower herb production in Guatemala

Propagation is by seeds, cuttings, or layering. Cuttings about six inches in length can be taken from mature plants, then rooted in sand. Maypop grows readily from seed—if one has patience. After harvesting the fruits, clean out the seeds from the mucilaginous fleshy aril surrounding them, then plant immediately. They may germinate late in the summer, or may sit dormant until the following spring. The experience of many who try passionflower from seed for the first time is disappointment, born of expectations that the seeds will germinate in a couple of weeks. Wait a year if you have to. The result of your patience and suspense will be worth it a few years later.

Propagation by layering can be achieved simply by removing the leaves from a small section of a stem in late summer, placing a portion beneath the soil, with a leafy end sticking out of the ground. Water well, and in a few weeks, the buried stem should produce roots. But wait. Keep the layer in the ground through the dormant months, allowing it to develop a full root system before transplanting. The layered cutting can be severed from the mother plant and placed in a new location. With a little luck and persistence, you will soon have your own passionflower planting. Of course, the easiest technique is simply to buy plants from a nursery. Young plants are often slow-growing, taking two or three years to establish. After that, watch out—it can entangle everything else in your perennial beds.

Passionflower as Food

In his “Thousand Mile Walk to the Gulf” John Muir speaks of the apricot vine (maypop) has having a superb flower “and the most delicious fruit I have ever eaten.” If you grow passionflower, you must taste the fruits. The fruits of the passionflower ripen from yellowish to light brown in color. The slimy aril covering the seeds is very sweet and fruity when ripe. The hard seeds can be separated from the pulp through a sieve or apple sauce strainer. Or if you are in the garden, you can pop open the ripe fruit and suck the delicious pulp from the fruit. Make sure that the fruit is not over-ripe. Perfectly ripe fruits are delicious . Over-ripe fruits ferment into a foul paste.

At the annual funding-raising auction of the Arkansas Native Plant Society a few years ago, I was the fortunate high bidder on two jars of maypop jelly. I know of no other native fruit whose flavor is best described as “indescribable.” The best maypop jam recipe can be found in Billy Joe Tatum’s Wildfoods Field Guide and Cookbook (Workman Publishing Co., Inc., New York 1976). Billy Joe’s book, which transformed wild edible from the realm of survival food to haute cuisine, also contains a delicious recipe for maypop punch, and maypop ice, a cool refreshing beverage with juiced maypops and pineapple sherbet. To make 10 half-pint jars of maypop jam, she combines 5 cups of gently rinsed maypops, with a 1/2 cup of lemon juice, one box of powdered pectin and 7 1/2 cups of sugar. Enough water is added to barely cover the fruit. Standard procedures for making jam are followed.

Passionflower was a minor food item of American Indian groups in the Southeastern U.S. Archaeological evidence shows that maypop seeds could be found at Indian camp sites over 5000 years old. Seventeenth century visitors to Virginia such as the Englishman William Starchey observed the harvesting of fruits from corn fields. Calling it maracock, Starchey described it as “of the bigness of a green apple, and hath manie azurine or blew kernells, like as a pomegranat, a good sommer cooling fruit.” It is unclear whether native groups intentionally planted the passionflower as a crop or whether it simply occurred naturally on the disturbed ground at the edge of the plot. It is clear, however, that native groups of the Southeast enjoyed this late summer fruit for many centuries.

Passionflower as Medicine

Passionflower never became an important medicinal plant in the U.S. Like many American medicinal plants, however, it is more highly revered in modern Europe than in its native land. In the second volume of his 1830 Medical Flora or Manual of Medical Botany of the United States the naturalist Constantine Samuel Rafinesque makes one of the earliest reference to medicinal use. He recommends a syrup of the fruits as a cooling agent for fevers. The leaves, he says are used externally, and the juice given to dogs to cure the “staggers or epilepsy.” This use was first recorded in 1787 by a German surgeon, Johann David Schoepf, who served with Hessian mercenaries siding with the British during the Revolutionary War.

In Europe, passionflower products are used as mild nerve sedatives and a sleep aid. The introduction of this medicinal use is credited to Dr. L. Phares of Mississippi who in an 1840 issue of the New Orleans Medical Journal, recorded its use. Remaining an obscure reference in the literature, Dr. I.J.M. Goss of Atlanta reintroduced passionflower into Eclectic medical practice in the late nineteenth century.

Dr. E. D. Stapleton writing in a 1904 issue of the Detroit Medical Journal summed up his experience in using passionflower tincture to treat insomnia “I would say that its action is best obtained in cases of nervousness due to causes other than pain-that it is slow in acting because it is not a narcotic, but a nervine and sedative. It relieves irritation of the nerve-centers and improves sympathetic innervation, thus improving circulation and nutrition, and is as a rule sure in its results-no bad after-effects, no habits formed”.

In the eighteenth edition of King’s American Dispensatory (1898), authors H.W. Felter and J.U. Lloyd characterize its action. “Its force is exerted chiefly upon the nervous system, the remedy finding a wide application in spasmodic disorders and as a rest-producing agent. . . It is specially useful to allay restlessness and overcome wakefulness, when these are the result of exhaustion, or the nervous excitement of debility. It proves specially useful in the insomnia of infants and old people. It gives sleep to those who are laboring under the effects of mental worry of from mental overwork.” Sounds like I need some myself.

It is interesting to note that while yellow wild passionflower (P. lutea) is very rarely mentioned in the medicinal plant literature, Dr. Phares of Mississippi is said to have used this small North American vine interchangeably with the common passionflower. I have made a tincture (alcohol extract) of both plants. They have a very similar flavor and fragrance. The fruits are decidedly different, though. Those of P. lutea are globular black berries, about 1/4 inch across. They have a much more acidic flavor than maypop.

Herbal Medicine Past and Present by John K Crellin and Jane Philpott (Duke University Press 1990) is based on extensive interviews over a seven year period with an Alabama herbalist, Tommie Bass. Bass, quoted in the text says, “Its the most wonderful sleep and pacifying plant, valuable for a nerve medicine . . . Any good sleeping medicine has passion-flower in it.”

Today the American passionflower is used in a number of proprietary phytomedicines (plant medicines) in Europe, used for “conditions of nervous anxiety.” A dosage of 4-8 g. of the herb per day in infusion (tea) or other methods of preparation such as equivalent extracts for internal use. Products are made from the fresh or dried whole plant (excluding the root). It is usually collected at flowering time. It is also widely used as a sleep aid. The fresh or dried whole plant as well as their preparations are also used in daily dosages equivalent to 0.5 to 2 g. of the herb, or 2.5 g in tea (about a teaspoon of the dried, ground herb). Preparations include tea, tinctures, fluid extracts, solid extracts, and even sedative chewing gums. Passionflower is also combined with valerian and hawthorn in products used in Europe to treat digestive spasms, gastritis, and colitis.

Like many medicinal herbs, the exact chemical components responsible for the plant’s sedative activity have not been definitively identified. Researchers have found small amounts of components known as harmala-type alkaloids in the plant, as well as compounds called flavonoids. In Germany, passionflower preparations were regulated to contain no more than 0.01 percent of harman alkaloids. Some believe the flavonoids to be active compounds. Still other researchers believe that substances known as maltol and ethyl-maltol may be responsible for the sleep-inducing and muscle relaxant activity attributed to passionflower. Generally it is believed that the sedative effect is probably a result of an interaction between the alkaloids and flavonoids found in the extract.

While the active constituents and mechanism of action of passionflower requires more studies, various studies confirm a sedative effect on the central nervous systems. The degrees of effect is dependent upon dose. Extracts of the herb inhibit fungi and bacteria. Studies indicate that the herb (or its extracts) relieves spasms, has a sedative effect, allays anxiety, and lowers blood pressure. The experience of numerous medical practitioners and herbalists in Western herbal traditions generally confirm the plant’s safety and efficacy.

Most of the supply of dried passionflower leaves either cultivated or wild-harvested in the U.S. goes to the European market. Farmers treat it as a weed in the South. USDA scientists focus on developing it as a new fruit crop for the U.S. Gardening enthusiasts appreciate the passionflower and subtropical passionflowers for their fantastic, colorful floral assemblage. Wild food enthusiasts, delight in its delicate, delectable flavor. And if you are a herb gardener, you’ll undoubtedly enjoy adding passionflowers to your herbary.

References:

ESCOP. 1997. Passiflora herba. In ESCOP Monographs on the Medicinal Use of Plant Drugs. vol. 4. Exeter, UK: ESCOP Secretariat.

Felter, H. W. and J. U. Lloyd. 1898 Kings American Dispensatory, 18th ed. 2 vols. Portland, OR: Eclectic Medical Publications, reprinted 1983.

Foster, S.1991. “The Passionflowers.” The Herb Companion (August/September): 18-23.

Foster S. 1993. Herbal Renaissance: Growing, Using and Understanding Herbs in the Modern World. Salt Lake City, UT: Gibbs Smith.

Foster, S. and J. A. Duke. 2014. Peterson Field Guide To Medicinal Plants: Eastern and Central North America. Boston: Houghton Mifflin Harcourt Co.

Gremillion, K. J. 1989. The Development of a Mutualistic Relationship Between Humans and Maypops (Passiflora incarnata L.) in the Southeastern United States. Journal of Ethnobiology. 9(2):135-158.

Hoch, J. H. 1934. The Legend and History of Passiflora. American Journal of Pharmacy. (May): 166-170.

Krellin, J.K. and J. P{hilpott. 1990. Herbal Medicine Passt and Present. 2 vols. Durham, NC: Duke University Press.

Mabberley DJ. 2008. Mabberley’s Plant-Book. Third Edition ed. Cambridge, UK: Cambridge University Press.

McGuire, C.M. 1999. Passiflora incarnata (Passifloraceae): A New Fruit Crop. Economic Botany 53(2):161-176.

Olin, B. R., ed. 1989. “Passion Flower.” The Lawrence Review of Natural Products. (May):1-2.

Speroni, E., and A. Minghetti.1998 Neuropharmacological Activity of Extracts from Passiflora incarnata. Planta Medica 54: 488-491.

Ulmer T, MacDougal JM. 2004. Passiflora: Passionflowers of the World. Portland, Oregon: Timber Press.

Vanderplank J. 1991. Passion Flowers (and Passion Fruit). Cambridge, MA: The MIT Press.

Weiss, R.F. 1988. Herbal Medicine (translated from German by A.R. Meuss). Beaconsfield, England: Beaconsfield Publishers Ltd.

Field Guide to Medicinal Plants Available NOW

The Third Edition of the Peterson Field Guide to Medicinal Plants and Herbs: Eastern and Central North America by Steven Foster (me) and James A. Duke are available at your favorite bookstore. | ISBN-10: 0547943989 | ISBN-13: 978-0547943985 | 456 pp., paperback | $21.00 |

The all new third edition of a Peterson Field Guide to Medicinal Plants and Herbs: eastern and Central North America. — The all new third edition of a Peterson Field Guide to Medicinal Plants and Herbs: Eastern and Central North America.

Roger Tory Peterson (1919-1996) wrote and illustrated A Field Guide to Birds: Eastern and Central North America, now in its 6^th edition, first published in 1934. He invented the modern 20th century concept of field guides, introducing generations of Americans to the flora, fauna and natural features of North America. Peterson Field Guides have now been for published 80 years.

The third edition of the Foster and Duke Field Guide to Medicinal Plants is expanded to include 60 new species not found in previous editions. The book includes 531 species accounts with information on 588 medicinal plant species. With 705 color photographs by Steven Foster, over 88% of the images are new. Over 66% of the plants in the book are native species, while 33% represent non-native, mostly European and Asian aliens.

Medicinal plants and herbs are all around us

Whether hiking along a remote Appalachian mountain trail or simply observing plants in one’s own yard, medicinal plants can be found everywhere humans live and travel.
Can we control invasive alien weeds by finding a use for them? Many homeowners attempt to eliminate weeds from their yards—dandelions, English plantain, and chickweed. Some call them weeds. We call them medicinal plants.
Some garden plants, such as English Ivy, are registered as ethical drugs in Europe, in this case for the treatment of coughs and upper respiratory tract infections.

Inspiring Conservation awareness:

A Field Guide to Medicinal Plants and Herbs provides a glimpse of the human experience with plants. Native medicinal plants from the eastern deciduous forest, including black cohosh, goldenseal, and American ginseng are among more than 150 native species that are still harvested from the wild and enter international commerce. Sustainable use of these valuable resources is paramount for future generations.
Conservation of these important genetic resources is informed by awareness of their medicinal value.
“Without knowledge there is no appreciation. Without appreciation there is no conservation.”

New Research, New Details—Reconciling tradition with science:

Uses have been thoroughly updated and revised, with more nuanced detail on historical use in pre-21st century America and elsewhere, including ethnobotanical details by specific native American groups, traditional use by American physicians and herbalists, and information on historic or modern use in Europe, China, and elsewhere.
Details on the latest scientific developments that in many cases reveal a rational scientific basis for traditional use.
Rather than use the internet or secondary references, the authors went to great lengths to scour the original references from which the information is derived, whether a 17th century renaissance herbal or the latest original scientific studies.
Since the publication of the second edition in 2000, worldwide research on medicinal plants has increased by a factor of at least 5-fold. Prior to the year 2000 a PubMED search for Echinacea in the title of a scientific paper returns 80 unique studies. A search for Echinacea in the title between 2000-2013 yields 443 studies.

Names, Distribution, Descriptions, and Flowering Times Updated:

The last decade produced a dramatic increase in the study of plant genetics leading to changes in plant taxonomy and family associations. New taxonomic designations are provided along with the synonyms of familiar scientific names from earlier works.
Plant biology and plant geography is dynamic, not static. We have revised and updated geographical distribution and occurrence details. Many non-native species have greatly increased in distribution, a disturbing but important data set.
A surprising aspect of revising data was the need to readjust the range of blooming periods. With the effects of climate change, some plants are blooming earlier (or in some cases later), which may reduce or extend flowering or fruiting, depending upon species and distribution range.

Updated Information on safety, toxicity and drug interactions:

The book contains appropriate warnings on those plants that can lead to poisoning or toxic reactions, sometimes even by handling the plant. Some plants, such as St. John’s wort are known to interact with enzyme systems that interfere with the absorption of prescription drugs, sometimes increasing or decreasing the drug’s effective dose. Important examples such as St. John’s wort are update to reflect that new research.

Cover of the 1st edition published in 1990.

First published in 1990 Steven Foster and Jim Duke’s A Field Guide to Medicinal Plants: Eastern and Central North America (Softcover: ISBN 0-395-46722-5) featured information on the identification and use of about 500 medicinal plants of eastern and central North America. It was the first modern comprehensive field guide to medicinal plants. The book included pen and inks by Roger Tory Peterson, Lee Peterson and Jim Blackfeather Rose. A 48-page color insert had nearly 200 photographs. With 366 pages it was the 40th title in The Peterson Field Guide^®Series. If you have the first edition, you don’t have the third edition. Simple as that.

Cover of the 2nd edition published in 2000.

In 2000 we produced a new edition of the title, this time calling it A Field Guide to Medicinal Plants and Herbs: Eastern and Central North America, with no line drawings, illustrated with photographs. Herbs had come of age by the year 2000. In 1990, annual herb product sales were about $250 million, and by 1990 they had surpassed $3 billion largely the result of the dietary health and supplement act on 1994, which created the regulatory category of “dietary supplements” and moved herb products from health and natural food stores into the mass market. A few years earlier, the infant internet also began to play a role in marketing and distribution. If you have the second edition, we think you will enjoy the all new third edition.

The Beauty of Gardenia

By Steven Foster |

As our Louisiana refugees from Hurricane Katrina can attest, what’s not to like about gardenias except for the fact that you can’t overwinter them outdoors in Northwest Arkansas? Like many plants in American horticulture, gardenia originates from eastern Asia, particularly warm temperate regions of China, southward, where broad-leaf evergreens thrive. The genus name Gardenia fortunately also serves as the common name for this evergreen shrub with, creamy white, single or double-flowered blossoms whose beauty is surpassed only by their intoxicating, heavenly fragrance. The delightfully-scented flowers are offered by florists in table arrangements, corsages, and boutonnieres. For the better part of two decades, I’ve had gardenias as container plants, bringing them indoors for the winter, taking them out in spring after danger of frost has passed. Photo gallery of single-flowered Gardenia from a plant grown from seed collected in the wild in mountains near Hong Kong.

There are 200 or more species of Gardenia found in tropics and subtropics of the Old World. That which we grow is called florist’s gardenia or cape gardenia Gardenia jasminoides. The cape jasmine arrived in England in the 1750s, and was named in 1761. The name “jasmine” as applied to this plant comes from a painting by one of the most famous of natural history illustrators, George Dionysius Ehret. Ehret, unsure of the plant’s identity, labeled his plate “jasminum” with a question mark next to the caption. Since gardenia flowers superficially resemble those of jasmines (trailing plants of the olive family) it was given the species name “jasminoides.” Gardenia is named for a Scottish physician and naturalist, Alexander Garden (1730–1791), who settled in South Carolina in 1755. During the American Revolution he sided with the British. In 1783, after the war was over, his property was confiscated and he returned to London.

The Chinese history of the plant dates back at least to the first century B.C.E., mentioned in the in the oldest Chinese herbal, Shen Nong Ben Cao Jing, attributed to the Divine “Plowman Emperor,” Shen Nong. The Chinese name, zhi-zi, applies to the plant as well as the dried fruit, which used in prescriptions in traditional Chinese Medicine for the treatment of jaundice, a use confirmed by recent research, that has continued for more than 2000 years.

Chinese history reminds us that American history by comparison is merely “current affairs.”

Ginkgo Leaves Falling

By Steven Foster.

The brilliant golden yellow leaves of the Ginkgo trees flanking the back entrance of our local post office, once they are ready to fall, will drop in a few hours time, raining from the thick branches like small fans twirling from the sky. After our first hard killing freeze last night, the Ginkgo leaves fell today.

Ginkgo tree with golden leaves on 11 November 2013

The same Ginkgo tree on 13 November 2013, minus its leaves.

The shriveling fruits, which look like half-sized wild persimmons, may persist for a few days after the leaves, then fall to the ground. Fruits are always a tempting curiosity. In fact, you can buy Ginkgo seeds as a food item in Chinese markets, but these have been prepared and processed to render them safe to eat. You should not be tempted to pick-up the freshly fallen fruits, which will cause contact dermatitis similar to the rash produced by poison ivy. The fruits have a fragrance that has been described as a blend between baby vomit and what a dog might leave on a sidewalk. That should be enough to entice you to leave them be.

I suspect that these trees were planted about the time the Eureka Springs Post Office building was completed in 1918, rather than in 1973 when the building was expanded and the service parking lot in the back was developed. The trees are of a fairly good size, plus for many decades most ginkgo trees available from nurseries in the United States have represented male branches grafted on to rootstocks. Within forty years after Ginkgos were widely planted as a street tree by the mid 1800s, female trees like those at Eureka Spring’s Post Office began to leave their bad smelling fruits on sidewalks. Female Ginkgos are simply not a neat and tidy street tree. Notwithstanding the beauty of the fall foliage, the fact that these two trees are females makes them a unique and interesting part of Eureka Springs’ heritage.

Beneath the Ginkgo tree, 13 November 2013

Ginkgo was common 175 to 200 million years ago, when dinosaurs roamed the earth. This primitive tree is considered the oldest living tree species on earth. Ginkgo is monotypic. That is, in the ginkgo family there is only one species in one genus — the only surviving member of the ancient and primitive ginkgo family—Ginkgoaceae. Ginkgo has been cultivated in East Asia for hundreds of years. Numerous reports mention the existence of large specimens, some more than a thousand years old, at ancient temples in Japan and China. The tree was first introduced to North America in 1784 in the garden of William Hamilton at Woodlands near Philadelphia. Mature ginkgos are said to reach over 100 feet in height. Its longevity as individual trees and a species in general can in part be attributed to its exceptional resistance to pests and resiliency to destruction by fire. It is also extremely tolerant of air pollution thriving in the harshest urban environments.

Ginkgo leaf extracts are highly complex, highly concentrated preparations with an average ratio of 50 parts ginkgo leaf to one part of the finished extract by weight. Numerous chemical constituents are found in the extract. Normally ginkgo leaf extracts are calibrated to contain 24 percent flavone glycosides (but may range from 22 to 25 percent) which are a relatively ubiquitous group of compounds found in numerous plant species. Another important compound group in ginkgo leaf extracts are mostly unique to ginkgo — the ginkgolides — including ginkgolides A, B, and C (around 3 percent) and bilobalide (also about 3 percent). As the oldest living tree species on earth, it is no surprise that it would harbor chemical components rare in nature. Perhaps these extremely complex, large molecules have helped it survive for eons. In addition, during the manufacturing process another group of compounds, ginkgolic acids, which are perceived as potentially toxic, are reduced to below 5 parts per million. Given the specific chemical make-up of ginkgo leaf extracts, it becomes clear why you can’t apply the results of studies with Ginkgo leaf extracts to a simple tea made from ginkgo leaves. Numerous pharmacological and clinical studies on Ginkgo leaf extracts have demonstrated a positive effect in increasing vasodilation and peripheral blood flow rate in capillary vessels and end-arteries in various circulatory disorders, varicose conditions, post-thrombotic syndrome, chronic cerebral vascular insufficiency, short-term memory improvement, cognitive disorders secondary to depression, dementia, tinnitus, vertigo, antioxidant activity, among other effects.