He soon became one of the most popular landscape artists of his period, working in many parts of the British Isles. Glendening particularly enjoyed painting views of the Thames, Surrey and Sussex in the Southern Counties, and in the Scottish Highlands where he enjoyed painting dramatic landscapes with lochs and cattle.
He exhibited at the Royal Academy, British Institution and Suffolk Street between 1865 and 1903.
His son and pupil was Alfred Glendening Jnr. whose work is very similar to that of his father. He painted in a broad and realistic fashion in a style similar to that of Alfred de Bréanski.