There are two primary ways I think this plant could be modelled: the route you appear to have gone is the first; a closed cylinder with the holes implied by black spots in the texture. At the very least the top of the model, if not the other holes as Kaziem suggests, should probably be slightly indented to increase the impression that they are holes. The second route is the one I suggest: an open cylinder with the texture applied to the inside as well as the outside. The holes would be created through an alpha map. (Edit: I also think the top of the cylinder should be alpha-mapped to match the holes). I did make a mistake in my drawing; the interior faces would have to diverge from the exterior faces at the joints, if the joints are modelled.

I also think the stalk should either be very pale or dark, as in the images shown, and appear dry and woody and perhaps frayed:

Edit: incidentally, I have the stalk flare too much at the top. As far as the general shape is concerned, I certainly think we should stick to Kaziem’s image.