Nonlimiting water range means that the amount of available water for a certain thing (like a plant or soil) is not limited and can be whatever it needs to be in order for it to grow or stay healthy. For example, if a plant needs lots of water, the non-limiting water range means that the plant can get as much water as it needs from the soil. When there is no limit, the plant can get all the water it needs to grow and stay healthy.