Dear Marie, If you have a damp to wet area, Cannas can't be beat for taking the heat, growing tall -some up to 12 ft and blooming all summer. Needing a bit more TLC are a variety of tall Dahlias to to D. imperialis approaching 20 ft. These are both available in a range of flower colors, foliage and heights. Best Jim On Mar 14, 2013, at 8:57 AM, desertdenial@hotmail.com wrote: > Hi John , > Crinum grows really well here and so do a variety of gladiolas. Those are > some of the tallest I can think of. >