I thought limes do flower and seed ok in the UK but the seed is often not viable, I have seen lime trees flower regularly but not where I now live.
I've got two types of comfrey, bocking 14 and a native wild one we've grown from seed which I assume will self seed. The bocking 14 is being grown in a place where I had a compost heap and is doing quite well but a native one I planted a couple of years ago has hardly increased in size, which I expect is to do with the poor soil. I am aware they may spread but as I can simply sythe them down and as the woodland was planted on old pasture I'm not worried about them spreading. On that note, whilst I'm careful not to introduce something illegal (rosa rogusa for example) I see so many people dumping garden waste about I don't worry too much.
I've got two types of comfrey, bocking 14 and a native wild one we've grown from seed which I assume will self seed. The bocking 14 is being grown in a place where I had a compost heap and is doing quite well but a native one I planted a couple of years ago has hardly increased in size, which I expect is to do with the poor soil. I am aware they may spread but as I can simply sythe them down and as the woodland was planted on old pasture I'm not worried about them spreading. On that note, whilst I'm careful not to introduce something illegal (rosa rogusa for example) I see so many people dumping garden waste about I don't worry too much.