Judy5cents, love your grandmothers garden, it resembles one I have been working on for the last couple of years. I am making single row flowers like yours but my neutral is white with white center. I purchased a good supply of 1 1/2 inch hexies for it and I am hand basting the fabric to the papers and then hand sewing everything together. I have a small plastic kit that I pick up and take in the car when we go almost anywhere and in the summer, sit on the porch working on some while the dogs are swimming and playing.
More recently I found a "rose star" on the web that I fell in love with and have made my own hexies then duplicated and printed on card stock at a print shop. The hexies start at 3 1/2" for the center of the star and then are cut into different sized pieces to reassemble. I am using a glue stick to form the fabric to the paper and then hand sewing the pieces together. So yes, I am addicted to hexies, love the look.