First, I used levels on the picture which really enhanced the colors and giving it a better blend of light and dark.
Then, using curves, I magnified the colors a little more, giving the darker brick wall a richer color, while brightening the sky slightly.
Using the channel mixer, I set all of the output channels to +116, with the others at -8. This really made the greens, reds, and blues pop in this picture.
Finally, I used the burn tool to bring out the leaves and sky, since they were rather dull in the original.