Plant Identification: Rooting cutting - What is it?, 1 by AcquiredCuttingsMan

AcquiredCuttingsMan wrote:
Hello. I\'m from the UK and I acquired this cutting from a public garden in North Yorkshire, UK about a month ago. The donor plant was about a foot high and it had roughly a loose two foot spread. There were no flowers or flower buds and I suspect that it was probably planted purely for its attractive foliage. This cutting rooted within a week or so in a plastic zip bag and it is now growing away well in a 3 inch plastic pot with roots visible through the drainage holes, and I suspect that it may now be ready to pot on or plant out into the garden. The only problem is that I\'m unsure what it actually is and I\'d like to find out how hardy it is. My garden is in USDA plant hardiness zone 7. I posted this picture on an online plant ID website and the result showed that there is a 58% chance that it is a Persicaria Maculosa, but when I do a picture search for that, I can\'t find anything with foliage that matches my plant. Please does anyone recognise it?