Jeanine M. Davis, Associate Professor and Extension Specialist and Richard E. Bir, former Extension Specialist (now retired), Department of Horticultural Science, North Carolina State University. This article was written in 1997 and is updated periodically (5/18/2022)

The American public has a longtime love affair with herbs. A few years ago everyone was grinding basil for pesto, stuffing rosemary in their vinegar bottles, and putting French tarragon sprigs on their chicken. Then they moved on to herbal wreaths, soaps, and potpourris. Now companies across the nation indicate that herbal medicines and aromatherapy are the fastest growing sales categories. The general feeling in the industry is that the public’s interest in herbs has not reached its peak and healthy growth is expected in the future.

So what can that mean for you as a propagator? Retail nurseries report that gardeners are very interested in growing their own medicinal herb plants. People are in the market for shade-loving perennials, such as ginseng and goldenseal; sun-loving plants, such as purple coneflower; and shrubs and trees, such as witch hazel and ginkgo.

The companies producing medicinal herb products, such as the capsules and tinctures you find in health food stores and pharmacies, have traditionally purchased most of their raw herbs from India, China, and the Eastern European countries. As the medicinal herb industry has matured, however, the companies buying these herbs have instituted new quality control efforts that include testing for active compounds, purity, and bacterial contamination. Many companies have found that foreign imports do not meet their new high standards.

This has opened up a market for American growers to produce large acreages of medicinal herbs. This, in turn, has created a market for the seeds and plants to produce these herbs. That is where you as a propagator can get involved with herbs. So let me tell you about some of the plants that are currently in demand and some of what is known about producing these plants.

There are several important points to keep in mind before you jump into medicinal plant production. One is that you are working with “new crops”. Thus, your county extension office will not have information packed bulletins on how to grow most of these plants. I encourage you to read everything you can about the herb plants we do know something about, and about plants that are similar to what you want to grow. Talk to the people at your local botanical garden and to herb enthusiasts. Mostly, you must rely on your own experience, horticultural knowledge, and “gut instincts.” Keep careful notes on everything you do and the results you obtain. You could quickly find yourself the expert on propagation of one of these little-known medicinal herbs.

Second, be very careful about where you buy your seeds and planting stock. This is a new industry and quality standards aren’t always what they should be. Check your sources out very carefully. If you decide to collect seeds and planting stock from wild populations, be certain to check on local regulations and the status of plants before you head out. Some of the more popular medicinal herbs are endangered or protected species in some states.

For any of the shade-loving plants, of course, you must provide shade. Commercial herb growers use natural shade or artificial shade provided by wood lath or polypropylene shade cloth. When using artificial shade, I recommend tall structures, about 8-9 feet tall, with two open ends for good ventilation.

What are some of the plants in demand? Right now, one of the plants in greatest demand is goldenseal; Hydrastis canadensis, a shade loving, herbaceous perennial. It is used for many purposes including as a treatment for AIDS, cancer, various digestive disorders, and to boost the immune system. It is native to North America and used to grow in abundance throughout the Appalachian region. Unfortunately, native populations have been seriously reduced by over collection and it is now a protected plant species in North Carolina and under CITES regulations for international trade.

Goldenseal has a rhizome by which it spreads rapidly and is easily propagated. In fall or spring, these rhizomes can be cut into pieces. Try to include an obvious bud on each piece, but research indicates that it is even more important to have good roots. Goldenseal produces a raspberry-like fruit, which is full of seeds. These seed require special handling, such as they cannot be allowed to dry out. Most growers find they get the best germination when the seed are sown immediately after they are extracted from the fruit. This, of course, is not real practical for the propagator.

Studies are underway at North Carolina State University looking at seed extraction methods, seed disinfection treatments, seed storage temperature regimes, and planting dates. So far, the best germination has been obtained from seed that had been held at 70 degrees F prior to sowing in late August or late October.

Studies are also being conducted on soil fertility, mulch, and spacing for goldenseal. For the fertility studies, goldenseal was grown for three years in forest soil amended to provide four levels of lime, phosphorus, and nitrogen. Emergence the first year was greatly influenced by lime application. Emergence was very low where the soil pH was lower than 4.8 or higher than 6.7. If the plants made it through that first year at the undesirable pH levels, they exhibited 90% or better germination the following years. Any supplemental nitrogen, reduced emergence that first year, but had little effect in the following years. The response to phosphate, supplied as superphosphate, was much the same. As with emergence, the plants were tallest around pH 5.5 and 6.5.

Goldenseal roots and rhizomes are the plant parts of interest to the propagators and the botanical ingredient companies. There was a dramatic response in growth of these parts to soil pH. The bottom line is, remember to keep pH around 5.5 to 6.5. These numbers will be refined as further research is conducted. Fresh root weight was inversely related to increasing nitrogen rate during the first year of growth. There were no significant responses to nitrogen rate after the second or third year, however. The response to phosphate additions was very similar.

Studies are now underway looking at spacing effects. Plants emerged first in the closest spacings of 2×2 inches and 4×4 inches. Mulch studies were also initiated in 1997. Plants grew best the first season with bark mulches, pine needles, and sawdust. Straw mulch resulted in poor growth and severe slug damage. Shade requirements are also being examined with plants growing under polypropylene shade providing 30%, 47%, 63%, 80% shade and wood lath.

So, as you can see–there was a lot we didn’t know, and still don’t know, about growing goldenseal. However, for those willing to try and work out the cultivation methods, there are good markets for goldenseal seedlings and mature plants for planting stock. There also is a limited, but growing market, for goldenseal plants for retail sales.

American ginseng (Panax quinquefolium) is another medicinal herb that has a long history of cultivation in North America. You will have no problem finding information on ginseng seed handling and plant growing. Ginseng seed requires very special handling and a stratification period of about 18 months. Like goldenseal, ginseng seed must never be allowed to dry out. There are a large number of suppliers of ginseng seed and roots for commercial growers. However, there are few nurseries catering to the home gardeners. A few enterprising growers have tapped into this lucrative hobbyist market. These plants sell for $12 to $25 a piece.

Other shade requiring medicinal plants in demand include black cohosh (Actaea racemosa)–a perennial shrub, fairly easy to propagate by root division or seed. The roots of this plant are used to treat various feminine disorders. Mayapple (Podophyllum peltatum) is another woodland plant in demand because of its cancer fighting properties. It is propagated primarily by dividing the roots in the spring because the seeds can be hard to germinate. The plant thrives, however, under cultivation. Bloodroot (Sanguinaria canadensis) has a pretty, early spring flower which makes this plant especially attractive to the retail market. Bloodroot can be easily propagated by seed or root division. Bloodroot is used in a popular toothpaste because of its ant-iplaque properties. It also has other antibacterial properties. It can be quite toxic, however, at low doses!

Chamaelirium luteum goes by many common names, including fairy wand, star grub root, Helonias, and devil’s bit. The plant is an erect, fleshy, perennial with a rosette of leaves at the base. Male and female flowers are borne on separate plants. This plant has not really been cultivated and we know little about its requirements. However, demand for this plant is increasing. The roots are used to treat a variety of feminine disorders. Any herb that can be of use to the aging baby boomers, especially to help them deal with problems related to menopause, prostate, poor memory, and low energy, will have a strong market!

A sun loving, field grown plant that does well for plant sales include all the different species of Echinacea, including angustifolia, purpurea, and pallida. The most common use for Echinacea right now is to help boost the immune system to prevent catching colds and the flu. Skullcap (Scutellaria lateriflora) is in demand as transplants for a field crop. It is easily grown from seeds. Skullcap is used as a sedative and to treat headaches. Calendula (Calendula officinalis) is a very attractive herb, commonly used in home herb gardens but also grown in large acreages. It is easily grown from seed. Calendula is valued for its wound healing properties.

If you decide that you want to get into the medicinal herb plant business, you need to know what is happening in the industry. My first recommendation is that you subscribe to some of the more popular herb publications. The demand for various herbs can change rapidly, and it is important to keep abreast of what is happening in the industry. For information on the industry in general, with emphasis on retail, look at publications such as the “Business of Herbs” and the “Herbal Connection”. Information of this sort on the wholesale and field grown medicinals is harder to come by, but “HerbalGram” and the trade publications for natural foods are good places to start.

There are extension specialists in many institutions, such as N.C. State, Purdue, and Virginia Tech, who have good information on herb production. Productions guides on ginseng and goldenseal and other information on herb production and seed sources are available on-line from NC State Extension Publications Library. Other institutions also have information on line, such as the New Crop website at Purdue. While you are on the Web, be sure to check out the HerbNet. that site could keep you busy for hours!

“ATTRAnews,” the newsletter from the federally funded program called Appropriate Technology Transfer for Rural Areas, is a publication that is useful to anyone looking at commercial production of alternative crops.

Some of the companies buying herbs and contract growing also can provide some useful production information. And some seed companies who sell large volumes of herb seed provide technical assistance. For example, Johnny’s Selected Seeds hired medicinal plant experts as consultants to help with their herb line and Richter’s Herb Seeds holds a growers conference every year. I also recommend that you join local and national herb associations. For example, the International Herb Association provides good networking opportunities, holds a national conference each year, and has regional chapters that can be a good source of information.

Currently the market is strong for medicinal herbs so many growers are jumping into it. But the ones that stay with it and find it profitable will be the ones who do their homework, grow a quality plant, and provide the service and prices the market demands.

Written by Jeanine M. Davis. Presented by Richard E. Bir at the International Plant Propagators Society Meeting Newport, RI, October 1997. May also be found in the Combined Proceedings International Plant Propagators Society 1997 47:39-41