QuestionSaw your answer to Doug 2007 about the "m" type of split leaf.
My two are also at least 25 years old and far too big for my house. They are very root bound. How do I prune them and if I can, I think I will also need to cut back the root systems.
AnswerKaren,
I am assuming that you mean a philodendron selloum. It is not possible to take cuttings from this plant. If there is more than one shoot I would cut one off at a time and cut it back by 50-66%. That should force it to send out side shoots. When it sends out the side shoots you can cut the original one off further if you wish. If the plant has more than one shoot you can then prun the second shoot.
To cut the root system back you need to carefully remove the plants fronm their pots and use a machete or very large knife to literally slice off the outside oof the rootball by 2 or more inches depending on how large the rootball is to begin with. Then put the plant back in a slightly smaller pot and put some fresh soil in the pot around it. You can root prune it once a year over 3-4 years and reduce the size considerably. Good luck.
Darlene