How do I change the desktop background color?

[germanix]

I am running Ubuntu12.04 with the default unity desktop (Ambiance). I really like the color of the splash screen at boot up. When the unity desktop loads, you first have that same splash screen color but then the ambiance theme takes over and the desktop background color changes to different hues. (light and dark patches). I do love the ambiance theme (icons and windows etc) and I do not find that the default color for the desktop is bad. I would just prefer a uni colored background for the desktop.
So really what I would like is for the desktop background to remain the same uni color as the splash screen or even the log-in screen with the grid of white dots would be nice as a desktop back ground.
Any ideas how this can be accomplished?
Appreciate the help.

[Lars Noodén]

Are you looking for something more complex than this:

right-click on desktop -> wallpapers -> colors & gradients

[germanix]

Well now that you mention it, i guess I am not seeing the woods for the trees. In reality all I want is a wallpaper that is the same color as the splash screen. I can try to match it but I was thinking along the line of just stopping the ambiance wallpaper to load on top of the splash screen color, as that loads first. So I thought you just change a line somewhere (edit it out) and that would be it.
I guess your way is more simpler providing I can get the color to match.
I also would like to try the grid effect from the log in screen would not know how to do that.

(edit) just tried colors and gradients as you suggested and it works brilliantly. Thank you for that. One sometimes tend to look for difficult answers where the simple answers are much better.