I must admit - I really love roses, but unfortunately the embankment at the fence only gets full sun for about four months of the year. So I do not think roses will survive there.
Not quite true - try David Austin roses. They have a huge variety. Roses will grow with only 4 - 6 hours direct sunlight a day - in summer. I have a wide selection of roses that get little sun during the winter (they are mostly hidden by an embankment) but during summer they put on a grand display. SA is very similar in climate I believe to SA (South Aust). I also have several under Japanese Maples -not the best place one may think - but the tree has grown a little larger than I had anticipated so early on it's development. I had planned on moving them in 5 - 6 years-but hey - they are performing wonderfully well. They are lucky to get any more than 4 hours a day during summer. However, because Austin roses have been developed in te UK the amount of sunlight is relative.....
What I really love about the variety he has is the perfume. Try one or two and if they don't work well - I figure you're only out maybe $50 at the most.
If you plant 900mm apart they will join up without any issues.
Aloe plants? Prick the Bejeez...s out of you and have a nice rosette as well....Good thing is the sap....helps with sunburn and the pricks (so to speak)

Can testify to the effectiveness of the 'thorns' - had some and I accidently put my forehead in one (don't ask) - anyhow I subsequently pulled them out.
Horticulturally yours
Tim
PS By the way - still lost on the failing of the fence - it appears to have broken a third of the way up or so - how is the ridding of the weeds the issue?
PPS I'm not even going to go there with the gun issue...