A gate blocked the way. It was very tall and very padlocked. I had a choice: climb over or squeeze under. I opted for the latter and carried on up the hillside, my track winding through oaks. The reward soon came: rounding the first corner I found the primroses. Hundreds covered the sunny bank, turning the green turf yellow – the primrose gardeners had been hard at work. I’ve long known that ants practise agriculture by herding and milking aphids, but I’ve only recently discovered that these fascinating insects are also avid gardeners.