Pictures would be extremely helpful.

I remember, it's called "Cordiline" It is used in the summer as a centerpiece. Mine has grown so well. It has become quite large and I wonder if it can be taken indoors.

Cordylines are easy houseplants, and of course can go back outside for the summer. I started with a wisp in a 4" pot four years ago. I just measured, and it's 42" tall from the top of the soil to the top leaf point. Mine is "Red Star" and I love it.

Why do you want to shear the top of yours?

It almost sounds like you are describing ornamental grasses, which are quite often used to add height to summertime potted plants. Don't shear them if that's what they are! Maybe you can identify what you have from some of these photos and then search on the type of care they need. Some need moist soil, some need dry. Most will need lots of sun, but some will thrive in partial shade. You may also be able to plant them outside, though that will depend upon the zone. Personally, I LOVE ornamental grasses! I hope this helps.

Here is a link that might be useful: Pictures of Ornmental Grasses

In my area narrow-leaved versions of cordyline and dracanaea are often described and sold as "spike plants" to use as the center plant in a container of summer annuals. I've seen them with labels that just say "Annual Spike" with no botanical name. Both look like grass, but are actually trees that eventually develop woody trunks. They can live many years with the right care.

If you think you have a cordyline, then try a web image search for that name. See if the photos match your plant. Mine came tagged with the proper name so there was no mystery. Pruning may induce branching. I have never pruned mine. For now, I like the symmetry of the single stem with its fountain of deep red leaves.

It is cordyline. The only reason I want to shear the top is because it's too tall and wide. I'm simply not sure if I can provide sufficient light for it. It's surprising how well it's grown this summer. I've never had one so big.

You must have given it exactly what it needed this summer, to grow so well. Congrats. :-) Mine has survived the winters I've had it with surprisingly little light.

I recommend you search on the houseplant forum for more info on cordyline. Since what you're talking about doing at this point is keeping it as a houseplant.

It was facing south all summer long. I would like to keep it for next spring. From what you wrote cordyline can survive relatively low llght, It's simply so big and if I cut it, what will it look like by spring. I guess I'll just bring it in and hope for the best. Maybe next May I'll write how well it did.

This follow-up is late, but it might help you. Sounds like you have cordyline since the plant is red-tinged. If you had the green plant, dracaena, you can grow it outside. I plant the "spikes" and they grow into 10-ft "palm trees." Sometimes they die because of a freeze, and sometimes they freeze and regrow. I never count on them to be permanent, but it is fun to see them grow to huge plants. At present, I have 3-yr-old dracaenas that lived through several days of snow and freezing rain last winter. The cordyline will grow similarly in a warm zone.,