A successor of the plein air Heidelberg School tradition in Australian art, Gruner is known for his high-key impressionist landscapes and his ability to capture the ephemeral effects of light.

[2] One of Gruner's winners of the prize, Spring Frost (1919), has since become his best known work, and is regarded as perhaps the most loved Australian landscape painting in the Art Gallery of New South Wales.

[3] Gruner was born in Gisborne, New Zealand, younger son of Elliott Grüner, a Norwegian-born bailiff, and his Irish wife Mary Ann, who died in 1922.

[4] In 1911 a small shop was started in Bligh Street, Sydney, to sell works of art produced in Australia, and for a time Gruner took charge of it.

In 1916 he was the winner of the Wynne Prize with a small landscape, Morning Light,[5] a painting showing the farm of Jim Innes at Emu Plains.

The effect of travel on his work was very noticeable: there was generally a good deal of simplification, more attention to pattern, and a freer and wider sweep of his brush.

The foreground is dominated by a dusty road and fence behind, running from bottom-left to the middle-right of the picture, with a range of tree-covered mountains behind the mainly treeless valley.