I found an official campsite which was much more to my liking. All the basics provided – showers, wifi etc – in a small orchard. The neighbours were friendly too – a Dutch man who had been widowed two years previously and had turned his car into a campervan in disguise with cunning little drawers that pulled out and turned into kitchens; another cycle tourist from Austria who was only carrying 20kg of gear on his bike. The Dutch man (called something like Shaman) made me a cup of tea and I provided biscuits.
The campsite was slightly noisy as still close to the road, but it took me no time to fall asleep.