keeping green grass green

I planted grass seeds last year and my lawn looked extremely green, except in some areas, where it looked yellowish or light green. This year, the yellow/ light green areas on the lawn are back. With closer observation, it looks like the green grass is growing over dead grass. Is there something wrong with the soil? How do I resolve this?

Light Green Thumb

light green grass is usually a sign of nitrogen deficiency. It can be other things. You could do a full soil analysis to make sure. Or, you could put a little of the organic lawn fertilizer on a patch and see how it does.