He bought 100 acres (40 ha) of virgin tussock land at Greendale in Canterbury in 1865 and converted them to farmland.

Adams was a pioneer in planting trials, obtaining seeds from correspondents around the world, keeping records and publishing the results.

He started planting trees in 1868 for shelter and fuel, and by 1908 had created an arboretum of 800 species.

His recommendation of Pinus radiata and other pines influenced early New Zealand forestry.

For 40 years, Adams taught Sunday school at Greendale, which began by teaching local children to read.