Question
Hey Ed,  I have two trumphet vines.  One is a number of years old and one just a few years old.

I want to keep them to a reasonable size.

shold I cut them back every year after flowering and if so how much can i cut them back?  Any special precautions?

Thanks

Answer
J,
Trumpet vines are one of the most prolific growers in the garden. Most people consider them an invasive and nuisance plant since they will grow anywhere and choke out other plants.
Do not be afraid of killing these vines with pruning them- I don't think it can be done.
Good luck.
Ed Gulliksen