2 quad mesh has strange brightness issues

For grass that I wanted to use in my level, I made a really simple mesh that consists of two quads. When I tried to put on a material that I was already using for other foliage in the scene, the colors were ridiculously bright. This prompted me to make the material darker, but even making the color far darker than any other foliage in the scene still produced very strange colors. I have no idea why this is happening, as this is not the first mesh that I have imported into UE4 and it is an extremely simple one.

Does lighting behave differently for these kinds of meshes? Does the Subsurface material type not work properly in this situation? Any help would be much appreciated!

It seems like the color I picked was too similar to the sun color, so it got too bright. Oops…