You could cut the fronds and use them as green filler in floral arrangements (They're short duration foliage, will shed pretty soon, but very pretty.) Or lay them down over the bed. Since it's a raised bed, you may want to put a protective cover over the box. Did you, the first winter? During the dormant season, the crowns can tolerate freezing - mine have been fine for years in Ontario winters that get very cold sometimes; -20-25F not unusual . We do have thick snow cover as a rule, which may help.
