Question
Having just moved into a 'new' house find that previous occupant  has tried to remove ivy which has grown over brickwork and plastic (upvc) windows.
This has left what best can be described as dead roots. I have no problem with with the brickwork, but how do I get these from the surface of the window's upvc without scraping and therefore scratching and damaging the shiny surface. (Any damage to the surface will only encourage dirt to enter and make them look awful).
You answer will be most appreciated.
many thanks

Answer
Hi Dennis,
Congratulations on your "new" home! I am glad that the previous owner at least saved you the time and trouble of removing ivy from the brickwork and windows. Ivy -- particularly English Ivy (Helix hedera) is a vigorously invasive plant that can not only smother nearby vegetation, it can also cause serious damage to brick work over the long haul.  

But you know all that already.

So, onward to your question about how to preserve the glossy finish of your UPVC windows!
I am sorry to say that this is a problem that a neighbor of mine has battled for several years (though it was she, not a previous owner, who let the ivy take up housekeeping on her UPVC windows...)
So.....since you really need to to SOMETHING, here goes:

The first thing I'd do is spray the remaining ivy residue with an herbicide that contains glyphosate (e.g. RoundUp or Brush-B-Gone), making sure none of it drips or blows onto any desirable foliage.  Do this several times (especially repeat after it rains) over the course of a few weeks. I know, I know, this stuff isn't "organic." If that's an issue for you, you can try clove oil or a solution of vinegar and water.  (Recipe: Mix 1 part vinegar to 4 parts hot water, pour the mixture into a sprayer and spray it on the UPVC. Let the mixture "set" for a few minutes and then wipe with a clean and smooth cloth.)

I have also heard of people using baby wipes or their powder laundry detergent to clean their UPVC without any problems.

Second, explore the various cleaning products on the market made specifically for UPVC materials.  For example, I have heard good things about Mr. Clean Magic Eraser. There are also products that you can order online, one called "GeoCel" and the other called "Rhino Rub." They advertise themselves as  cleaning and restoring lost shine to PVC products.

They key, as you know, is to avoid abrasive cleansers or scrubbing surfaces.

Dennis, I am afraid that plumbs the depths of my knowledge.  I do wish you all the best, and I think you will eventually succeed in restoring the appearance of your UPVC; it may just take time and, possibly, several attempts over several seasons.