Where to use plants as diffusors?

I have about 6 potted plants that I can use to help diffuse the sound around my Merlin VSM-M speakers to hopefully achieve a deeper, wider soundstage. Unfortunately, between the 7' space of the speakers is a 55" RPTV which can't be moved (I sometimes use a down quilt covering the plastic screen for serious listening). The speakers are out about 3.5 to 4' from the wall, and quite distant from the side walls.

The plants have decent dense foliage, and they are all at least a couple of feet tall.

Any ideas of where to best place the plants to diffuse the sound to minimize reflections?
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i've got them at the first order side wall points and have fairly well stuffed my big glass bay window full. helped a lot more than you'd expect. I have to add that most of the plats were at least half up the wall if not floor to cieling. i'd put short ones up on a table so they are at the level of your tweets
Being only "a couple of feet tall" they might not do much, but suggest putting them in the corners.
Good listening!