Any color that has a large component of black is hard to create with lighting. I don't know your scenario, but one way to kind of 'trick' lighting is by the color of the wall/brick/etc you're shining against.
You can play around with the RGB values (something like 70/0/0 or 80/0/0 or 90/0/0) to replicate maroon, but it's not real doable. You'll basically end up with varying shades of dark red. The light output won't look the same color as a phone/computer screen.