I know that there are at least two people who are interested in giving Flower Power a try and I thought I’d post some tips to help match and sew y-seams.
I start creating a flower by sewing the 3″ side of the 4 tumbler sections onto the 3″ x 3″ square, leave a 1/4″ seam allowance on all sides. I draw a 1/4″ seam allowance on the 3″ squares and triangles, this helps when matching points. ** Reduce your stitch length to approximately 1.8mm when sewing bias seams **.
When inserting your diamond piece between the tumblers, your first seam needs to start at the center sewing out toward the edge. I use a pin and drop of Elmer’s School Glue (washable!) then press to secure so it doesn’t shift.

I’m using Elmer’s CLEAR School Glue

Set glue with an iron.

Sew the first seam from the center out to the edge. I always backstitch y-seams!!
Stop your seam 1/4″ from the edge and backstitch. Pivot your diamond piece and start your second y-seam a 1/4″ from the outside edge (no glue necessary).

Sometimes I use a pin to ensure the edges stay in line.

Finished Y-Seam

I press all seams toward the darker fabric. As you can see above, I sewed all four diamonds onto this block, oops! I really didn’t think everything through and have to remove a diamond from each block in order to sew them to each other.
I have all my flowers sewn and am in the process of joining them together, will post an update tomorrow.