Embodiments of a method and a system are provided to create a uniform layer of a substance such as a hydrogel or other fluid substance underneath the soil surface with minimal or little surface disturbance to the plants, the plant roots and the soil located on or slightly below the applied surface area. It is to be clearly understood that various different embodiments may be employed to deliver a variety of different substances to the soil, and such substances may be gels or liquids. The presently preferred fluid substance is currently a hydrogel, and the present illustrated and described embodiment may be employed to inject hydrogel into soil but other fluid substances may be injected as well.