90 days. [Introduced before 1920 as an improved strain of 'Purple Top Yellow' (pre-1850) selected for a smaller top, shorter neck, globular shape, and sweetness.] 'American Purple Top Yellow' is a Swedish turnip of American origin. It has long been the standard for home and market use. Roots should be harvested when 4 to 6" in diameter. Flesh is mild, yellow, fine-grained, and firm. Pkt. (3 g)