Jeffrey Beasley, Sanders, Kayla, Sexton, Mary, Kuehny, Jeff S., Stagg, Jason, Fontenot, Kathryn, Chen, Yan
Jeff Beasley, Yan Chen, Jeff Kuehny, Kathryn Fontenot, Kayla Sanders, Jason Stagg and Mary Sexton
It’s that time of year again when we seek relief from the hot, humid weather by drinking a cold glass of tea. Although tea is a common beverage, second to only water in consumption for Americans, the majority of leaves used to brew this summertime concoction are still mainly imported from Asia. Countries such as China, India, Nepal and Sri Lanka have long histories on how best to produce and process tea. However, in the past decade there is a renewed interest in how to grow, process and brew teas in the United States because of its potential health benefits and consumer demand for local foods.
Tea is produced from the leaves of Camellia sinensis, a relative of camellias, which are commonly grown across the southern United States as a shrub. The tea plant is an evergreen perennial shrub that is adapted to warm, humid climates. Therefore, climates in the southern United States should be suitable for growing tea.
In parts of Asia, tea has been grown for thousands of years. Plants are spaced so that over time they grow together to form a hedge, and leaves are harvested by pinching them off for processing teas such as green, oolong and black. Refining the steps for processing different teas has occurred over hundreds of years. In fact, many tea-producing countries believe the strong cultural roots of tea production make it a national treasure. In the United States, tea production is still in its infancy, with tea producers in about 17 states. Southern Mississippi and Louisiana currently have several commercial tea growers, and acreage is expected to increase over time as more farmers begin to learn and explore tea as a potential crop for their area (Photo 1).
In Louisiana, tea planting is beginning to grow with the help of the Louisiana Department of Agriculture and Forestry through a U.S. Department of Agriculture Specialty Crop Block Grant to the LSU AgCenter. AgCenter researchers and extension agents are assessing market demand and consumer preference for locally grown or processed tea, evaluating varieties best suited for Louisiana and educating the public about tea as a potential specialty crop in Louisiana.
Similar to blueberries but not related, the tea plant is adapted to more-acidic, well-drained soils in a warm, humid climate. However, there are lessons to be learned on how to best propagate the tea plant. Unlike ornamental camellias that are propagated through stem cuttings grafted to root stocks, the tea plant can be easily propagated from seeds. But because this can result in differing genetic stock that could eventually lead to shifts in plant characteristics and tea quality, the major method for propagating the tea plant is through rooting of stem cuttings (Photo 2).
Success of rooting stem cuttings has varied across cultivars, with some rooting more easily than others. At times the rooting process can be frustrating for growers because the callus of the cuttings can take time to form and root development is slow. One factor that appears to affect tea plant propagation is pH. More basic pH appears to slow or prevent callus formation and thus root development. Therefore, simple propagation studies have been initiated to examine the role of pH on tea plant propagation with the idea of providing assistance to growers to speed transplant production.
Using different substrates amended to adjust pH from basic to acidic, tea plant stems were placed into each substrate and evaluated over a 12-week period for callus formation and root development. Initial results indicate more-acidic, well-draining substrates are the key. However, callus and root formation were not uniform, even as the substrate pH was acidic. The pH of the water used for keeping the cuttings moist during propagation was above 8, which is believed to be the primary reason for lack of uniform rooting. The water quality from underground water supplies in some parts of Louisiana has a high pH, which can often lead to issues with propagation and transplant production. After adjusting the pH of the water, tea plant stem cuttings rooted much more uniformly. Thus, adjusting both the rooting substrate and the water quality is important to producing quality tea plant transplants for field production
Continued research and extension efforts in several aspects of tea production are currently underway with collaborations with growers and a regional tea research team, all of which will provide much needed information to support a growing local tea industry in Louisiana and across the United States (Photo 3).
Jeff Beasley and Kathryn Fontenot are associate professors and Kayla Sanders and Mary Sexton are research associates in the School of Plant, Environmental, and Soil Sciences. Yan Chen is a professor and Jason Stagg is a horticulture instructor at the Hammond Research Station. Jeff Kuehny holds the Ola Cook Holmes Professorship in Horticulture and is resident director at the LSU AgCenter Botanic Gardens at Burden in Baton Rouge.
(This article appears in the summer 2019 issue of Louisiana Agriculture.)
Photo 1. Tea production field consists of more than 6,000 tea bushes at the J&D Blueberry Farm in Poplarville, Mississippi. Photo by Yan Chen
Photo 2. Tea plants grown from cuttings at the Windmill Nursery in Franklinton, Louisiana. Photo by Yan Chen
Photo 3. Tea producer David Baron (second left) and assistants discuss pruning height with Yan Chen (middle) at the Fleur de Lis Tea Farm in Amite, Louisiana. Photo by Asija Rice