(Blue is on one side of the spectrum, yellow is in the middle. Between them â¦ is the transitional color green. Any color that adds blue to yellow takes it into the green.)   Blue and yellow are primary colors. When you mix them, you get the secondary color green.The more blue you have in the mixture, the darker the green.  Yellow and blue make green It gives you dark green When you mix blue and yellow you get green.It depends on how much blue and yellow you use to make it a light green or a blue-green.he more blue you have in the mixture, the darker the green.   Yellow and blue make green It gives you dark green When you mix blue and yellow you get green. It depends on how much blue and yellow you use to make it a light green or a blue-green.