Answer: It's not clear to me exactly what you are looking for, but there are plants sold under the common name "spikes" that are used in containers for height. They have fairly thin, long arching leaves. Some are in the genus Cordyline or Dracena. There are green spikes, and there's also a reddish bronze color that is quite striking. Do a Google Images search on Cordyline container and the first page will show some examples (Cordyline australis or Cordyline terminalis Red Flash). If that isn't what you are referring to, please feel free to send another question to the Q&A site with more detail. Enjoy your container gardening!
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