Since about the late 1500s, a bushel of wheat has cost within an order of magnitude of £1. By contrast, in the late 1500's a farmhand's wage was 1 pound + room and board.

Right now it's £5.60, but that says more about the decline of the British Pound than an increase in the price of wheat.

Massive food price deflation has been one of the wonders of the modern world. Hopefully the last few years were only a small blip on this overall trend.