Coptis, also known as goldthread, is a tiny herbaceous plant that is closely related to buttercups. It is not commonly grown as an ornamental plant, but is valued by herbalists as a medicinal species. Growing coptis is a way to produce your own herbal medicine and participate in the conservation of this increasingly rare species.
Goldthread in the Garden
Coptis is a long-lived perennial plant that spreads by underground rhizomes to form colonies. It has has finely cut leaves growng just a few inches tall and tiny white flowers. The most beautiful part of the plant is what's underground, however. The rhizomes are a golden yellow color, hence the name goldthread, and are the part of the plant with active medicinal properties.
Goldthread is not an easy plant to grow, as its physical environment has to be just right. It needs rich, moist soil and cool conditions. It is typically found in the wild at higher elevations and/or northerly latitudes, so planting it in the shade on a north-facing slope is the best bet if you are gardening in a hot climate. It often grows in coniferous forests, so if you have a grove of spruce, pine, fir or other hardwoods to shelter it, your chances of success are even better.
Coptis can be transplanted from an existing patch or propagated by seed. If you're dividing an existing patch, be aware that the roots are very fragile and should be moved with as much soil around them as possible. To grow coptis by seed, sow it in a lightweight seed mix and keep moist in a cool environment. Germination can take months, so be patient.
When planting, plan on amending the planting soil with equal parts compost unless it is a location with perfect topsoil already, such as an established forest. It is best to put the plants in the ground in the cool weather of spring or fall.
Maintain a layer of mulch around the young plants. Gathering duff from around the base of the trees in an established coniferous forest is a great way to mimic the conditions in which coptis grows in nature. Regular irrigation is also crucial - there is no need to drown the plants, but make sure the soil stays evenly moist throughout the growing season.
Pests and disease are not problems with coptis, so much as giving it the precise cultural conditions that it needs to thrive.
Varieties for Purchase
There are medicinally active species of coptis native to both North America and China, but they are very similar in appearance and growing methods. Choosing which one to use may depend on which you can obtain seeds or transplants of more than anything else, as these species are uncommon in the nursery trade. That being said, the following are seed companies and nurseries that have a few varieties in their product catalogs; availability varies, so contact the companies for additional information.
- Plant Delights offers potted Japanese coptis, a variety that grow to six inches tall and is tolerant of boggy conditions; if it's out of stock, click the "add to wishlist" button after creating an account, and you'll receive an email when it is back in stock.
- Botanically Inclined sells seed for one of the North American species, Coptis trifolia, which forms a mat of evergreen foliage two to four inches tall.
- Z.W. Organic Seed Group Company sells seed packets for the Chinese variety of coptis, which is the one most commonly used in herbal medicine and has been harvested on a large scale in China, threatening the wild populations of the plant. Go to the order tab to search the inventory.
Networking with herbalist associations and native plant conservation groups is another way to obtain coptis plants or seed.
Herbal health care is an increasingly popular approach to well-being and coptis is one of its most trusted remedies. Demand for the herb has caused wild populations to become threatened, so nurturing a patch of your own is a great way to keep it around and have some to share.