Petite blue and yellow blooms on a light yellow background. Cheer up, buttercup! The pretty Buttercup collection by Whistler Studios for Windham Fabrics is filled with delightful bouquets, pretty tossed flowers, and stripes of colorful leaves. In a springtime palette of blue, yellow, and white, with navy and jade accents, these fabrics will make you feel like you’re strolling through a flower garden!