The first solution would be to buy a longer set of curtains. Curtains typically come in a few different lengths, so choose the next longer length than your current curtains. You can either let the extra length “pool” on the floor for a flow-y look, or you can hem them to the correct length. (If you’re not much of a seamstress, you could use a fusible bonding material to “hem” them without needing to sew anything.)
Looking beyond the traditional with wallcoverings can create a truly standout design presence. "I do think I might have scared [architect Ken Linsteadt] a little bit when I announced I was planning to install two levels of green floral fabric on the walls of the grand salon," says Ken Fulk of his Sonoma Valley lakeside retreat, yet the fabric gives the high walls a richness that wallpaper alone might not have achieved.