Often the biggest problem with farms trips is finding ones that the owners will allow you to use!
Nothing beats a face to face request. There was a strip in deepest Cheshire, not far from here, that
AFAIK hadn't been used in a long time, and the farmer had a bit of as reputation as 'an awkward bugger'. As it's the nearest 'airfield' to SSD towers, I wanted it in the log book.
One Saturday morning I pedaled round there on my bicycle and knocked on his door:
"Hello. I'd love to land at your strip in our Chipmunk. Any chance you'd be happy for me to do that?"
"Um, OK, I suppose. When?"
"This afternoon?"
"Um, yes... OK"
Rode home, drove to the airfield and wheeled out the aeroplane, flew in to the strip! Even Manchester ATC were helpful (the strip is in the Control Zone).