Friends, I should have noted that BOTH # 20 & 21 are totally hardy in Zone 5/6. Both get up to 30 in tall in bloom. Plant immediately in rich soil, cover lightly and water well. Should germinate in spring. Best of Luck Jim James Waddick 8871 NW Brostrom Rd Kansas City, MO 64152-2711 USA Phone 816-746-1949