I would isolate the large bluebell print with a couple near-solid fabrics, so it doesn't get lost. You could place it next to the one on the right, but those other two prints, while they "coordinate" beautifully, just don't have enough contrast. They really blend together too much. So choose a pattern where you can place the low-contrast fabrics apart from each other.
You could use a pattern like this one - where the floral print is showcased:
The large scale print is used in the center and the small scale print at the edges beyond the lattice - and the right hand fabric could be one of the lattice fabrics. Use the other for a border and the flag on the back. Just an idea....
Something like that would work well too - you can fussy cut the large squares and let the strips that you cut for the smaller pieces just fall naturally.