Q.Orange Trumpet Vine
For many years a trumpet vine has been flourishing along my side fence but, owing to the shortage of rain off and on over the last 3 years, the vine suddenly sprang up right through the base of several of my standard roses. The vine has sent its roots about 4 meters underground and also under a cement path. Where it has come up by the cement path which borders my rose garden I have cut it off and painted with mineral turpentine which stops it for awhile, but then more shoots come up..but the real worry for me is my precious roses which are all over 50 year old. How do I stop the trumpet vine from sending vigorous roots coming right up through the base of the roses? I wouldn’t dare use roundup or anything like that. When I cut the vine off right at the base of the roses it sends up more vigorous shoots than ever.
You must be talking about Campsis radicans, an aggressive vine in garden soil. I don't think there is anything you can do except prune out unwanted vines. One vine that may better suit your needs is Carolina jessamine, growable in AU zones 1-3. Here is some information: https://www.gardeningknowhow.com/ornamental/vines/carolina-jessamine/growing-carolina-jessamine.htm