"Bottle green" refers to a shade of dark green, which is also sometimes called "tartan green" depending on the kilt hose manufacturer. "Bottle" is not something that refers to a specific range of colors, it's just a descriptor used for that particular shade of green, like we have "navy blue" and "charcoal grey" and "kelly green."

And the minor colors in a tartan are simply those colors which there are physically less of. Accent colors, if you will.