I have had two or three in my time, and they hate doing it in the middle of the day.
Garden photographers always prefer to hot-foot it to my door before dawn – or when sun, slanting over a sea of catmint and alliums, is definitely over the yard arm.
The most dedicated was perhaps Jonathan Buckley. When he lived in Dulwich, for one whole summer and beyond he would swoop down to my Sussex garden in a battered old white Citroen.
At one point we agreed that I would phone him at some ungodly hour to let him know if there was hoar frost on my agapanthus. I had to trek down the garden en chemise de nuit , a muddy fleece and gardening clogs in pitch dark to find out, of course. There was, and he was there like a shot, well before the crisply seed-heads thawed just after dawn.