I found this in my garden 2 years ago and it has survived 2 harsh winters. It is now 20cm high and 60cm across. The plant is "sticky", very like a common weed, Galium aparine, but has no burrs and in the summer is covered in clusters of really pretty pink flowers. The plant doesn't die down in the winter. The stems become very fragile at soil level. I would like to propagate it as I'd be really upset if it died. Can anyone help,please?