Nancy, glad that there was no damage beyond a few mashed impatiens.

I found when trying to pull them out that working around the base of the roots and removing as many of the rocks that they had worked their way under made it easier to pull them free. (And of course since I had positioned the rocks to hold the baby plants in place, they immediately incorporated them into the root system and kept going.). So that’s one of the secrets of prying them loose. Reach underneath and work the rocks loose first. Good luck on getting them out easily.