The tall spadix of the titan arum plant remains upright because it is filled with cobweb-like support fibers.

References

"The tall grey spadix [of the titan arum], which is filled with cobweb-like support fibres, becomes flaccid, topples forward and droops over the margin of the spathe. The spathe itself contracts inwards and its upper margins start to twist round the lower part of the spadix, clasping it so tightly that a huge water-tight bag is created." (Attenborough 1995:136)

Book
The Private Life of PlantsBBC BooksFebruary 23, 2017
David Attenborough