The best thing you probably could do is start spraying everything out that you dont wont. You could start spraying now with Round-up. Spray it at about 2-3 ozs. per gallon of H2o. Spray your spots in your yard where you have the bermuda or crab. Keep it killed out for the rest of the year. Yes, you will kill some of your Augustine.  You want to try spray the weeds everytime they try and come back through.  Once you get them cleaned out, then next year you can work on growing in the spots with Augustine. You can reseed it or buy sprigs or plugs.  St. Augustine generally likes 2-4 pounds of nitrogen per year per 1000 square feet. Do not over fertilize which may cause it to yellow.

The first thing you should do is make sure that the area is not low.  If so, fill with dirt to bring up to grade. Then you can lay your gravel.  Plastic or landscape fabric is not needed.  Plastic want allow water through and the fabric has holes in it so weeds will find their way through it.

Make sure you are spraying your dormant oil rate as the label tells you.  When you spray the oil, cover the whole plant including the underside of the leaves.  Keep your spraying temperatures between 32-90 degrees.  If the oil or insecticidial soap still doesn't work then you should try liquid sevin.  Sevin can be bought at any local hardware store or landscape supply stores.  Just follow the label.  Keep up with the honeydew that the scale leaves behind.  This will help for you to tell if they are still active after you have sprayed. 

Anytime this month of January or Febuary you could prune back your Crapes.  Depending on how tall and big they currently are, I wouldnt cut back as much as 50%.  I like to try and cut the new growth from the previous year. Usaully that can be around 3-4 feet. This can help them from getting leggy and from bending over from the weight of the blooms.   --PRO

To start with, leave the last flowers on the plant. These will turn into hips(or seed pods). This will make the rose bush think it's done for the season and start to go dormant.  You can thoroughly water around the plant before freezing. Then when it freezes up, the bush will take care of itself.  Thick mulch around stalk is good to protect the graft(if it's a grafted rose).  Don't worry about mice, most likely they have already found a warm spot with plenty of food for the winter.

Yes you can.  It will give you a nice green color throughout the winter.  Use a high nitrogen content, Ex. 21-8-5 or 24-18-8.  Or some places offer a winterizer fertilizer.  I would put it out around the middle of November.