Pictured(far left): Dr. Elaine Ingham

Organic Farming and Soil Regeneration

Dr. Elaine Gingham of Soil Food Web has used Gro-King Garden Sprayers for scientific field test delivery of live fungi and microbes onto various plants and crops. Click below to read more about the results of her experience using Gro-King Sprayers.

Deep Root Injector

In recent years, the soil drench technique has become popular among organic gardeners, as a way to infuse live microbes and nutrients into the soil around plant roots. The challenge presented by this method is that there is no accurate way to determine the depth to which solutions actually penetrate the root ball.


For this reason, Dr. Elaine Ingham, world-renowned micro-biologist and President of Soil Food Web, commissioned Gro-King Garden Sprayers to design and build a Deep Root Injector, to her exact specifications.

The result is a high-grade stainless steel tool that is interchangeable with the TRW Spray Gun via the use of matching quick-connect fittings. The Injector has a 42” rod and a sharp, cone-shaped tip with four equi-distant holes, through which solutions can easily be dispensed deep into the root ball and surrounding soil. 

Injection Site Pattern

The Injector’s T-shaped stainless steel handle has durable, commercial-grade grip pads that ensure ease of use and prevent the palms of the hand from becoming sore/bruised. This makes it possible to use the tool for extended periods of time in larger garden plots.


The Injector handle also contains a solid brass trigger valve, allowing the operator to control the flow of solution while maintaining a firm grip on the tool. As is the case with the TRW Spray Gun, releasing the trigger not only stops the flow of solution, it also activates the auto-shut-off switch on the pump, thereby extending battery life.


When working with trees/shrubs/vines, Dr. Ingham recommends starting 2 ft. from the base/trunk of each plant and creating 4 equi-distant injection sites around the plant. Injection should be continued outward at 2 ft. intervals, doubling the number of sites to form a concentric circle pattern, (see diagram) with the final circle of sites being at the edge of the plant canopy, or just slightly beyond it.