The High Range is situated in the Devicolam Taluk of Idukki District (10º 5' N, 77º 4'E). The altitude of the district varies from 950 to 2200 m. Although the total area is about 320 km only, there is a lot of variation in the annual rainfall. On the northern edge of High Range (Top Station), the average rainfall is in the region of 1300 mm, elsewhere in the western end the average rainfall is about 7000 mm. The unusual variation in rainfall may be attributed to the peculiar configuration of the land and numerous parallel spots across the north-south edge of Western Ghats.

The temperature during day time rises to about 30º C and during nights in winter months drops down to 5º C. A large area of tea is damaged by frost during winter months every year.

The estates are clustered around the town of Munnar, which is about 145km from Cochin. Estates are situated mostly on the inner slopes of a basin-like plateau. The highest point in south India, also the tallest south of the Himalayas, is the Anaimudi peak at an elevation of 2695 m. The Eravikulam National Park, 17 km from Munnar, is home to a fantastic array of exotic wildlife, including scores of elephant, gaur, buffalo, spotted deer, monkey and tiger. It has the world's largest surviving herd of Nilgiri Tahr, the majestic and proud mountain goat of the High Range.

The Regional Centre at Munnar advises on all aspects of tea cultivation, plant protection, crop production and processing of tea. The laboratory is equipped to analyse soils for pH, EC, etc and root knot eelworm infestation. Several experiments relating to harvesting, infilling, inter planting and row inter planting, agronomy and pest control is being conducted here.