Those barrels are upagainst a brick building south side to boot,I finally cleaned them up well after christmas ,they were still green...A super micro climate...Always warm..I cant grow Verbena here very well ,It loves it down there. I ve got a baggie of seed to scratch in the stones,I keep forgetting it. I will get more photos of it as it develops,more or less a wild flower patch,no plans just what ever where ever,by the seat of my pants..
Everyone have great day