Little Scarlet

Little Scarlet is, according to Wilkin & Sons Limited, a strawberry. It is American by origin but is grown only in Britain.

This tiny berry is approximately one fifth the size of a strawberry of today, similar in size to the Alpine or Wood strawberry. The plant was brought to Britain in the 1900s by C.J. Wilkin, a member of the family who own the Wilkin & Sons conserve manufacturing company in Tiptree, Essex, following a visit to the United States where the plant grew wild. The company claims to be the only commercial grower of this fruit anywhere in the world. The Little Scarlet Conserve sells in around fifty countries at prices up to eighteen US Dollars for a 12oz jar.

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Wikipedia