50 days. Lyon proved to be one of the best tasting Swiss chards in our trials. The glowing, lime green leaf color contrasts nicely with other varieties. The lush plants have thick leaves up to 9 ½ inches wide and over 1 foot long with the color of new spring growth and the delicate, tender texture to match. Brilliant stalks are pure white and a broad, 1 inch wide. With its mild flavor, Lyon makes a good stand-in for spinach.