Aerial roots (more!)


    Aerial roots. The use and purpose of aerial roots could well start
an interesting discussion amongst the Aroid-l group. So far only a few
comments have been made but widely differing views have been offered
as to what should be done with the Philodendron "Xanadu" aerial roots.

    We've grown Philodendron's in a garden setting for many years
mainly with the help of three metre iron bark stakes or where there is
room attached to trees. At one stage we had twenty odd different
plants growing up a single pine tree which in itself give an
indication as to the versatility of Philodendron's as pine trees
aren't the greatest of trees to grow anything on. (Resin ect.)

    Aerial roots appear to serve a number of different purposes the
most obvious being to attach the trunk of the plant to whatever
support it's growing on. (perhaps these shouldn't be called aerial
roots ?? ) On the larger (taller) multi stemmed plants masses of roots
overlap each other growing into any crevice that can be found making
the plant pretty hard to remove.

    Other aerial roots from higher up on the plant seem to develop as
the plant grows. We have had some metres long, hanging free (from the
tops of trees) and as thick as your little finger. These seem to serve
only one purpose and that is to supply nutrient to the higher parts of
the plant. Eventually they always reach the ground and develop very
large root systems, larger then the original plants root system and
can spread out over\under a large area of ground.

    I've no doubt that these aerial roots eventually take over the
roll of "feeding" all of the plant. Often with the more mature
Philodendron's we find the bottom 40cm. of the trunk has rotted away
and the only contact the plant has with the ground is through it's
aerial roots.

    Other thoughts. As the plant grows the trunk is usually much
thicker at the top then at the base, plus it has much larger leaves
(depending), perhaps there isn't enough room (bottle neck) to supply
the necessary amount of "food" through the original trunk and root
systems hence the development of a supplementary feeding system.

    Back to the P. "Xanadu" aerial roots question. Without any
hesitation I would leave the lower roots alone, redirect the middle
roots into the potting media and leave the higher roots to develop as
they will. Eventually they will grow down into the media and nearly
always into another plants pot or territory.

    If you feel like experimenting a little next summer with one of
your "Xanadu's" that has aerial roots, wack off all the leaves down
one side, unpot the plant and lay it on it's leafless side in a shady
part of the garden placing the odd aerial root into the ground. Go
back at the end of summer, dig up the roots and see for yourself what
has happened.

    Peter.





Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index