Answer: Your zip code places you in zone 6B or the warmer part of zone 6. The blue beaked yucca or Yucca rostrada is considered hardy to zone 5 so should be fine for your area (However in your area it should be planted in the ground -- not in an above ground container -- for winter survival.) Yucca should remain green year round, however in severe winters there may be some foliage damage or discoloration by springtime. That would then be trimmed off to tidy the plant.
The ornamental grasses turn tan or brown when freezing weather occurs in the fall. They are then routinely cut back to ground level in either late fall or early spring and regrow during the spring and summer. Often they will flop over during the winter if not trimmed back.
The sedge maintains a presence all year, but in colder winter climates may be killed back to the ground in winter. This would require it being trimmed off in the spring.
I hope this helps.
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