It might be hard to fit the bush in that small of space, meaning it could crowd out other plants and block the sun. I guess the only way to find out would be to try it, but I would be cautious when picking the square/squares to plant it in. Make sure it's on the north side of the box and it might work fine.

I'm sure the plants would like the raised bed. There is no reason why they couldn't be grown in a raised bed. I have no idea what 'by the book' means. If you want to confine them to 'a square', presumably 1x1, the question would be: why?

Dan

Polly, my peonies would each take up 4 squares if they were in the SFG. Mine are in a raised bed that is L shaped, about 20 ft long by 4 ft wide. (When I first read your post, I was thinking about zinnias, so did not get the full picture at first!)

The peony root/tuber itself fits inside a square foot, but, when full of blooms, they spill over everywhere, even with plant supports in place. Then, after they bloom, you have about six months of just foliage. I don't cut my old foliage off until new shoots start to come up in the spring.

Still, we can all do what we want. I plan to put Sugar Baby watermelons in the end boxes and let the vines grow out on the walkway. The result should be more melons than last year, when we were hunting for them in the weeds.