Plant Growth and Development of Bush Tea as Affected by Nitrogen, Phosphorus, and Potassium Nutrition

Abstract

Bush tea (Athrixia phylicoides) belongs to the Asteraceae family. It is a popular beverage used as an herbal tea and as medicine for cleansing or purifying the blood, treating boils, headaches, infested wounds, and cuts, and the solutions may also be used as a foam bath. In some parts of South Africa, people drink bush tea for aphrodisiac reasons. Bush tea was grown under varying N, P, and K levels in all four seasons to determine the seasonal nutrient requirements for improved plant growth. Three parallel trials for N, P, or K one at each season were laid out in a randomized complete block design (RCBD) with six treatments replicated eight times. Treatments consisted of 0, 100, 200, 300, 400, or 500 kg·ha–1 N, P, or K. Parameters recorded were plant height, number of branches and leaves, fresh and dry stem mass, fresh and dry root mass, stem girth, fresh and dry shoot mass, leaf area and percentage leaf and root tissue N, P, and K. Results of this study demonstrated that, in all trials regardless of season, N, P, or K nutrition increased bush tea fresh and dry shoot mass, plant height, number of leaves, number of branches and leaf area. Regardless of season, the optimum level of N, P and K fertilization for bush tea on growth parameters was 300 kg·ha-1 N or P and 200 kg·ha-1 for K. No significant differences in number of flowers and buds (fall and winter), stem girth, fresh and dry root mass as well as fresh and dry stem mass were obtained.