Okay . . . here's my take on this . . . You have a very nice composition here. In fact, I wouldn't even try to add leaves or grass to the dirt behind this group. It looks like you used some sort of non-round 100% soft brush to do your cloning (in the background, right above their heads). Pretty good, but I think you need to try a different, simpler approach to your cloning.
I cropped out the bottom, but kept the image an 8x12 aspect ratio. I didn't feel the bottom help the photo at all.
I copied your picture into photoshop and used size 15 round brush @100% softness. Opacity 100%, flow 75%, Alignment: UNCHECKED
Using the Rubber Stamp (clone) tool I sampled an adjacent areas to the left and right of the sections I wanted to fix and clicked-clicked-clicked my brush over a section to clone from the source. Don't drag here because doing so will fuse the fine texture that you want to clone here. Notice when you use the tool un-aligned you'll always clone from the same source every time you click and reclick.
For the color correction:
First thing I notice is that the contrast is low, and your whites, as in the boys pants are very bright. There's not much pixel information to work with there. That is to say the RGB recipe for areas like the WHITE parts of the pants would be 255,255,255 or nearly so. That being the case we would only get shades of gray with no variation if we toned the pants down . . . so we'll look for other areas to kick-up.
I used a technique that is great for those who get a kick out of the mysterious things that photoshop does. I'm not really sure what's going on, but it works well enough for shots like this one:
With your flattened image open in photoshop, duplicate the background layer so you have an original image to revert to.
Go to Image>Mode>Lab Color. This uses a recipe for color that is NOT a combo of RGB . . . Lab Color actually separates the "color" info from the lightness/darkness info, the "L-channel" or luminosity channel. It then uses a ratio of Green to Magenta "a-channel" and Yellow to Blue "b-channel". -Hence "L-a-b".
Next, with your image layer selected, go to Image>Apply Image
In the Apply Image control panel, change the Blending Mode to Overlay. Now in the Source section, use the Channel drop down. Choose which channel seems to look like it might give you what you want. I like the "a" channel here, HOWEVER I lowered the Opacity in the Blending section down to 40% for this image.
I don't really know what's actually going on in the Apply Image engine, but i like it sometimes!
After this conversion and correction, go to Image>Mode>RGB to convert back to RGB mode, so we're Jpeg friendly again.
I opened the Levels tool (Image>Adjustments>Levels) and slid the black triangle slider to the right for 17 more points of black to fix the contrast. Using the Contrast tool would have added white levels too. There more than enough white in this image.
I then ran Smart Sharpen (Only in
PS CS2+) with Amount=68 / Radius=1.0
Here's my result, I hope you like it: