I have recently moved into my new new self build house and have 2 banks of soil either side left over from the initial dig, these banks are also form the borders of the site.however they are very wild and overgrown, I have tackled them this summer with a strimmer and they look fine but I want to try control them and plant shrubs and flowers next year to show off the border of the house, I have a few bulbs planted(daffs/tulips), but now its covered in wild grass and thistles, is my only option to spray and kill these. I would love to plant some shrubs, fruit bushes etc but I worry if I spray and kill everything will it kill the boundry mounds for a season. they are both 35 mtrs long and 2 mtrs high so digging is hopeully not an option .