Thanks to Therese for pointing out the historical possibilities with Google Earth. There's a 1945 image, which is so unclear as to be meaningless. Apart from that, the earliest is this one from 2002. The chief interest is that the double plot next door, to the West, was paved over even then. I suspect this is what has led to the waterlogging - all the water falling onto that area running down into my plot.
It also suggests that nothing much changed between 2002 and 2015. The fruit bushes to the East were taking up a lot of room, but the beds were being cultivated in the northern 2/3 of the plot. The absurd old shed is there, and there's something else in the midden area.