How can we preserve biodiversity while meeting consumer demand for natural products? That’s a question many growers ruminate on, including those who raise and sell herbs.

Tackling that topic is Susan Leopold, Ph.D., executive director of United Plant Savers. United Plant Savers is a nonprofit that focuses on research, education and conservation of native medicinal plants, fungi and their habitats.

Leopold began by quoting E.O. Wilson, the biologist, naturalist, ecologist and entomologist known for developing the field of sociobiology: “Our economy is our environment and our environment is our economy.” Those in horticulture are well aware of this fact.

She then noted there are 31,000 known plant species used by humans for food, fiber, art, construction or ceremony. Medicinal plants make up 17,810 of that total. Another staggering figure is that 60% to 90% of medicinal plants are wild harvested, and Leopold said this industry has a huge impact around the world.

“We really are data deficient so we really need to gather that,” she said. “The plants we use range from endangered to threatened to extremely common.”

Leopold noted that those in this niche of horticulture want transparency in their supply chains. The Columbines School of Botanical Studies offers a Wildcrafting Checklist, which asks those harvesting wild plants to ask questions such as “Do you have the permission for collecting at the site? Are there better stands nearby? Is the stand healthy? Is wildlife foraging the stand? Is the plant an annual or a perennial? Are you in a fragile environment?”

Growers are more interested in cultivating their own plants so they can control some of those issues, and the herb industry has grown tremendously in the U.S. – 12 consecutive years of growth, according to Leopold. Per Business Wire, the United States Herbal Supplements Market size was estimated at $2.246 billion in 2021, $2.565 billion in 2022 and is projected to grow at a compound annual growth rate of 10.62% to reach $4.116 billion by 2027.

However, of the 65 top native North American herbs, only 80% are seriously cultivated – leaving herbs like goldenseal, black cohosh, false unicorn and slippery elm overharvested and depleted in the wild.

“If it’s being cultivated, who is cultivating it and are they being treated fairly?” Leopold asked. “Growing and harvesting yourself is really ideal. You want to get as close to the source as possible. I do see herbal businesses as being a part of the solution.”

Those who cultivate herbs can help create botanical sanctuaries, according to Leopold.

And “becoming passionate about herbal medicine is a gateway to activism for native plants and ecosystem restoration,” she added. “As the plants heal us, we should look at how we can give reciprocity to the planet.”

Those interested in learning more about the herb industry are invited to visit the International Herb Symposium website at

by Courtney Llewellyn