I've no political axe to grind. All I have to share is my personal experience, and maybe you would consider that "apocraphal". I live in a part of the U.S. that has a climate much like that of London, U.K., but with rainfall closer to Manchester's  The last three years I've beeen harvesting ripe tomatoes in my backyard garden up until the date I am writing this. I still have tomatoes on the vine right now, and no frost so far.