I could've sworn this edit already existed but couldn't find it again.. if it did exist. Since I use these plants all the time- and the game plants & her huge plants can be placed with the cheat- I went ahead and edited them.
If you can't use "setquartertileplacement on" then these edits won't do you any good. If you can? Download them and stop using "boolprop snapobjectstogrid false" to place these outside of the tile! :) Bossy, aren't I?
I left the grid lines on to show that the plants aren't in the tiles. :)