The effect of Si4+−N3− incorporation on Ce3+ doped RE3Al5O12:Ce3+ (RE = Lu3+, Y3+, or Tb3+) garnet phosphors is described in this report. The addition of Si4+−N3− leads to distinct low-energy Ce3+ absorption and emission bands that are assigned to Ce3+ ions that have N3− in their local coordination. The combination of the typical Ce3+ emission in garnets with the low energy Ce3+ emission band results in a broad emission spectrum suited for white LED lamps with low color temperatures and good color rendering using only a single phosphor. The low-energy Ce3+ emission band has stronger quenching at high temperatures, a potential limitation. The mechanism for this quenching is discussed.