The present disclosure provides a liquid delivery apparatus for a planter unit. The liquid delivery apparatus is used to deliver fertilizer during crop planting. The apparatus is configured to attach to a planting device. The liquid delivery apparatus includes a tube which receives a liquid from a reservoir and delivers that liquid to the ground. The liquid flows through a passage extending down the tube. On the end of the tube proximal to the ground, the tube includes an injector with an aperture extending down a center axis. The aperture has a diameter smaller than a diameter of the passage. The injector also includes a tool receiving aperture that is collinear with the axis. Together the injector and the tube are no larger in diameter than the fertilizer tube alone. In this configuration the delivery apparatus is sufficiently compact and strong to be placed close to the ground without interfering with disks or be permanently deformed by debris.
