Because of high temperature and less rainfall in mid-summer, new tea gardens in tea production area of the south Yangtze River are more susceptible to drought and weeds, which badly affects the growth of tea. Field experiments were conducted to study the functions of different kinds of covering materials in new tea gardens. The results showed that in mid-summer, the black membrane mulching, non-woven fabrics cover and grass cover significantly decreased soil temperature. When high temperature lasts for 7 days or more, soil water contents of black membrane treatment and grass mulching treatment were significantly higher than control without mulching materials. Mulching could significantly inhibit the growth of weeds in tea garden. The growth of weeds in the treatments of black membrane and the non-woven fabrics was significantly lower than that in the treatments of white membrane and grass mulching. All mulching treatments could significantly reduce the weeding cost. The most effective treatment in this aspect was black membrane mulching. The treatment can save 8 550 yuan/hm² and save 6 370 yuan/hm², if the cost of plastic film cover is excluded. Black membrane mulching has the best effectiveness in reducing soil temperature, increasing soil moisture, controlling weeds growth and reducing the cost of weeding, followed by the treatment of non-woven fabrics and grass mulching. Therefore, black membrane, non-woven fabrics and grass are recommended as mulching materials using in mid-summer tea gardens.