Merton Knave is one of a series of apple varieties developed by the John Innes institute based at Merton in the middle of the 20th century. (This same institute was also involved in the development of the "Malling-Merton" MM106 rootstock). The apples ripen towards the end of August and are an attractive red colour. The flesh is white but like some other early varieties (notably Discovery) the red skin can sometimes bleed into to the flesh.
Although developed to offer commercial potential for the important early-season English apple market, it did not succeed in displacing Discovery and Worcester Pearmain.