Blending two layers

[brad daggy]

I know it's probably simple. Could anyone tell me how to blend two tiles. One is black. and the other is black going to dark orange. I tried overlaying one tile, creating a marquee, then gradient from dark to dark orange, but I didn't like the results.

 

[SignBurst PCs]

add a vector mask to one of the layers and use the gradient tool (black and white) to create the "blend"