Wonder if you could advise when I should harvest gourds, growing in my unheated greenhouse in W Yorkshire. Planted late, the biggest is only the size of a tennis ball, but I'm not sure if they will deteriorate as the weather gets colder, and I want to dry and varnish them. They keep producing flowers which I'm removing, and the leaves are beginning to get patches of mould, so I take off the worst of those. Haven't grown them before and don't know what to do next - they are mixed gourds.