I'm with the others, to not add in the sashing. With the striped blocks you have enough going on that the sashing isn't going to do anything for it.
And I THANK YOU .... I have some hearts made that I've been wanting to use for a quilt, and wasn't sure how to join them together as I'm limited in the background fabric. I think your striped squares have just given me the answer!
Plus ... the colours are perfect for another quilt I'm going to do ... I received a "Save the Date" wedding invitation in the mail yesterday. Lavender and turquoise hearts fell out. So since then I've been thinking about using those colours for their wedding quilt.
Please be sure to show us pics as to how you continue and finish off this quilt! It's lovely! :)