Abstract: A method for modulating plant growth is provided whereby seedlings that are grown in containers such as blocks are fertilized at lift. Prior to fertilization, the block, which has numerous plug cavities, is restrained. The seedlings, which are grown in plugs formed in plug cavities, are supported and a bore is drilled into the bottom of the plug. The bore extends to the top of the plug to produce a small port, which serves as a port for expulsion of air during the injection operation. The fertilizer is measured in a metering roller and is then pneumatically injected into the bore in the plug. Upon completion of the injection, the bore is closed to reduce the loss of fertilizer from the plug. The various operations may be automated or performed manually.

Abstract: A drill/injector combination is provided to inject plants that are grown in containers such as blocks at lift with plant growth modulators. The drill/injector combination is comprised of a seedlings holder, a block restraint, a cavity tool apparatus, a metering apparatus, an injection apparatus and optionally, a bore closing apparatus. The combination may be manually operated or may be automated.