Seethawaka Wet Zone Botanical Garden - Avissawella

Seethawaka Botanical Garden, or Seethawaka Wet Zone Botanical Garden, is one of the five botanical gardens in Sri Lanka. The other four are Peradeniya Botanical Garden, Henarathgoda Botanical Garden, Hakgala Botanical Garden and Mirijjawila Botanical Garden. It is the most recently constructed botanical garden in Sri Lanka. The garden was opened to the public in late October 2014.

Seethawaka Botanical Garden is situated on the Puwakpitiya-Thummodara main road, at Illukowita, adjacent to the Indikada Mukalana Forest Reserve at Avissawella. The 32 ha (79 acres) garden has a cool temperate climate.

A beautiful stream flows through the garden, which sustains the existence of various wet zone plants. The tree cover is made up of large Terminalia arjuna trees.

The garden was established in 20th century as a plantation for Rubber and Tea, which was owned by a garden known as "Pannaagula". But most of the land area was abandoned on that time, which was overtaken by Land Renew Commission. The construction of the Botanical garden commenced on 2008. The total land area of the garden is 105 acres (42 ha).

The garden mainly serves as a research area for different universities around the country. It is also used as a conservation area for threatened and vulnerable endemic plant species in the Sinharaja Rain Forest region. Improving export floriculture, ex-situ conservation of wet lowland plants, and bamboo cultivation are also promote in the garden.