Yet another British/American English difference. What most Americans refer to as their "yard" would in the UK be called the "garden". "Yard" is only used in British English in this sense only for a paved or perhaps gravel area, either an area used for parking vehicles, or an area surrounded by buildings (a courtyard or the area between a house and an outbuilding such as a stable, garage or barn) or for the very small open space between a terraced house and a back alley, or the open area in a factory or storage facility (a builder's yard or a timber yard, for example). More or less any grassed area (however well maintained) or any deliberately included greenery will elevate a back yard to a back garden.
The figurative experssion "in my/your/his backyard" to mean "very close" either geographically or, more rarely, conceptually is however commonly used in British English.
In a builder's yard, "yard" is commonly used tout court to refer to a cubic yard of materials sold in bulk such as sand and gravel: "Oi, sort us two bags of dust and a yard of sharp, mate."