Cherry Rose Sunflower Seeds. The fastest maturing sunflower we have seen at only 40 days to flower. A great cut flower with beautiful cherry-red flowers with lemon tipped petals. Plants grow to 150 cm (5') tall. With all sunflowers avoid drought stress and fertilize with 15-5-15 or similar analysis. Nitrate based nitrogen is better than ammonia based nitrogen. Stop fertilizing when flower buds form. Adequate soil moisture is important at all times and avoid overhead irrigation so as to keep the foliage dry. Space plants far enough apart to ensure good air movement over the foliage. Cool nights help the plant form a good solid stock.