Huge, 5" doubles, on sturdy, bushy plants. Zinnias add bold, vibrant color to gardens. The more you cut, the more they bloom! Heat-loving and very easy to grow. Zinnias are among our customers' cherished favorites. Start indoors 4-6 weeks before last frost, or sow outdoors where plants are to grow, when soil is warm. In hot lower central and deep southern states, sow midsummer to avoid mildew and enjoy glorious color all fall and early winter.