Placed plants deleted from round roofs and new plants impossible to place

I have also been having the issue of not being able to place plants on curved roofs. I play with all packs, no mods, no cc. I did find 1 plant that will place on every spot on a curved roof the Lovely Lavender Bush. It will place even with bb.moveobjects on or off.  Dry Rose Bush, and Ground Fern will almost place everywhere with bb. off. They will place everywhere with bb. on.