Average tea yields in China are low by international standards and are extremely low when compared to yields obtained on experiment stations. This paper reports on a ten year plant density trial undertaken by the Tea Research Institute in Hangzhou, Zhojiang Province. The green tea, vegetatively propagated, clonal variety used in the trial is called "Longjing 43". At the high densities used, this variety has yields more than ten times greater than the average for Zhejiang Province. Four different plant density levels were used in the trial. The economic analysis examines the performance in terms of conventional investment criteria: SNPV, Perpetual Annuity, B/C ratio, IRR and the Discounted payback period. The optimum time to prune is also calculated for each of the trials and sensitivity analyses are undertaken using various assumptions as to the relative performance farmers might attain.