Comfrey

I took a cutting a couple of years ago from a plant I seen growing on some wasteland because it was covered in bees and it’s now it’s about 1m tall. I didn’t know what it was until recently. I like the plant and it’s located the top end of my garden which is half way into being turned into a wildlife patch. I have read it can be grown from pieces of the root and was thinking about dividing it and covering the border in front of the fence with it. Are there any reasons I should not do this?