Think of a border as the frame around your pieced painting. It will stop the action of the overall pattern and can direct your eye to the most important parts. Plus, one or more borders can give your eye a place to pause before heading back into the active body of the quilt.
In some cases, a border will be a continuation of the pieced center. In that case you may want a thin border, or sashing, between the two to give your eye a resting place, as well as to accent a particular color used in the piecing.
We often see beautifully pieced tops with borders that just don’t work. Usually it’s because the border fabric is too weak or too strong for the rest of the quilt.
For example, the border on the following quilt is too busy and not strong enough in value and color to complement the quilt top. A less contrasty fabric in a deeper color would complement the quilt nicely.
“Spring Celebration” quilt. Get the free pattern here.
Audrey and Diane at The Cloth Parcel have written an excellent article about choosing quilt borders. We especially like their tip about auditioning border fabric, but there are other good points as well.