70-84 days. Tall Double Mix strawflower seeds grow some of the most recognizable summertime blooms both indoors and out! Strawflower Tall Double Mix seeds are an indoor favorite for growing dazzling color through the season, or for drying and complimenting fresh cut bouquets and arrangements. Strawflower Tall Double Mix seeds promise brilliant 2-3" blooms bursting with dozens and dozens of tiny petals. Tall Double Mix strawflowers grow easily from seed and are known to thrive in gardens prone to heat and drought throughout the southwest.