Thanks for the great explanation, applestar. I will keep that in mind if and when I actually see insects.
All I have found so far, is very little insect webbing around the leaves and roses but I have yet to spot any insects.
Some of the stems as you can see in the pictures posted above (of pink knock out roses) have some brownish looking patches on them (doesn't look like black spot to me) and I'm not sure if they are what you call canker stems or which version of them but I can't seem to find any pictures online that are similar to mine.
I will post a picture of the stems from my other pot as well. As you can see, the stems at the base are all wooden-like (I apologise for using these amateur slash ignorant terms -- I am obviously new to all of this). Are they supposed to be like that or are they supposed to be light green? This pot seems to have many more thorns as well (it's a red knock out rose pot). I fear these roses have been infected with something that can no longer be fixed... It really hurts me to see them in this condition and to have to cut the stems and dying roses
I would also like to get someone's opinion about watering (evenings or mornings?) and whether spraying water is necessary or harmful.
Thanks as always,