100 Years of Tea Research: Contributions of Tea Research Institute of Sri Lanka and its future role

Declining soil fertility is a major issue that the Sri Lankan tea sector is facing along with the aging plant stock, which act as a vicious cycle.

- BY PROFESSOR JANENDRA De Costa

Aging creates bush death creating open spaces (vacancies) in the plant stand, which are highly susceptible to erosion during rainfall.

Inadequate soil conservation measures exacerbate erosion and loss of fertility. In maintaining soil fertility, soil organic matter (SOM) plays a crucial role by increasing the soil’s capacity to retain water and nutrients added as fertiliser.

Higher temperatures in the low-country, where a substantial portion of the tea production comes from, increase the natural decomposition of SOM leaving very little in the soil unless it is supplemented with organic material such as loppings of shade trees or prunings from tea bushes. The TRI-recommended GAPs for soil fertility management are not practiced optimally by a majority of smallholders who contribute 75% to Sri Lanka’s national tea production. In order to address this issue, the Ministry of Plantation and community infrastructure, the TRI, the RPCs and the smallholder representative organisations have come together to initiate a comprehensive set of practices for regenerating soil fertility in tea plantations.

This programme for ‘regenerative agriculture’ is supported by international organisations as well.