I'm not an expert, but I am think not to do sashing, maybe two borders of two shades of green would set it off nicely! Maybe a scalloped border ...

What a great find...how lucky to have that. I agree that sashing would make the blocks really stand out. I like the idea of using green as a compliment to the leaves too.

Where will you display this. You may want to match the colors depending on the background in the room. I was thinking soft pink.

Beautiful..

If your feeling venturous try like small, small hst or double sashings on each block using not all the same color sashing for all blocks but use the two colors your mom used for each flowers..They would all be different and each block would stand out by its own color..

As it is a quilt which will bring back special memories of your mum when you look at it...why not try and sash it with a colour that you associate with her...what was her favourite colour or did she have a dress or coat she loved.
My mum adored green, all shades and had a red coat that I loved her in.....see where I'm going...wishes you much love with it...whatever you choose it will always be special.

WOW
what a great find !!

It's going to be stunning! I can't wait to see it finished.

those are really great

Pretty! Perhaps soft greens will help to set it ~

Oh I am so happy for you! What a treasure :)