Grow Heirloom Zinnias - Plant Purple Prince Zinnia Seeds A beautiful and elegant purple hue, Heirloom Purple Prince Zinnias look amazing when planted en masse, or combined with other bright colors like Envy and Orange King! Sure to create a show-stopping effect in your garden! A favorite of crafters, florists and gardeners alike, Zinnias are easy to grow annuals, preferring warm weather and full sun!