I'm not sure what causes the problem but I suspect it's a WB issue and/or reflection from your light source (both daylight and flash are quite blue)

Also, when you photograph something that is basically the same color your camera auto WB will tend to be wrong (actually, I've used a picture that is very similar to your rose picture to intentionally make my camera select the wrong WB in a blog post I wrote a while ago)

You said you you can't play with the WB much more without blowing out the red, well, fortunately there's another way to remove the blue cast - you can use curves on the blue channel only to remove the blue cast.

I don't have Photoshop on this computer so I used Paint.net that is free and also somewhat underpowered compered to Photoshop or even GIMP.

In the first image it's easy because there isn't really any "real" blue there so you can drop the entire blue channel without hurting the image, for example:

You probably should mask off the Ferrari logo so you don't change it's colors.

For the second image it was a little more difficult because if I just drop the blue channel the white glare on the flower will become yellow.

So, I've duplicated the layer, converted to grayscale, used levels to leave only the white glare in the image and used it to create a selection (using the magic wand in global mode) for the original image - I've then used curves to lower the blue channel and I've got this:

There's still an hint of blue there but much less than the original image and it's not bad for about a minute of work with a program that doesn't even has proper making support (I could have done better with more time, the masking was a little off).