How Deep Does Deep Root Fertilization Go

And Why is it Needed


How deep does deep root fertilization go? Short answer, about a foot into the ground. Read on to learn the long answer.

Fertilization vs. Deep Root Fertilization

You may be familiar with fertilizing your lawn, but what about your trees? Reaching the roots of trees requires more than sprinkling fertilizer around the trunk. Tree care companies use special equipment and solutions to reach a tree’s root zone, which is deeper than a lawn’s.

Trees in a forests shade out grass and other plants to weed out the competition for nutrients. Unless your lawn is full of trees and shade, it’s a much harsher environment for roots. Another feeding solution is needed to overcompensate. This is where deep root fertilization comes in.

What is Deep Root Fertilization

Trees respond to fertilizer differently than your grass. Nutrients need to travel deeper for a tree receive the benefits. Apply a slow-release fertilizer directly to the roots. Either inject liquid fertilizers into the soil or pour dry fertilizers into holes drilled into the root zone. Be careful not to over-fertilize, as this creates health issues as well. Gauge the need for fertilization by measuring annual growth, noticing visual symptoms, and/or chemically analyzing the soil or leaves.

During deep root fertilization, a high-quality nutrient solution is pressure-injected into the root zone of a tree to help aerate and provide oxygen to the roots. The soil injection begins just below the surface and goes to a depth of about 12 to 14 inches. Space out these soil injection sites about two to three feet apart in a grid pattern around the canopy area and beyond the drip line. Repeat these injections once or twice a year if needed. If you notice any root damage, soil compaction, or other health problems, consider increasing the frequency to help improve root conditions.

Ongoing Deep Root Fertilization

Roots thrive wherever oxygen, nutrients, and moisture are present. If deep root fertilization is noticeably improving tree growth and soil testing shows higher nutrient levels, keep doing what you’re doing. If there are certain plant health concerns or nutrient deficiencies present, contact the specialists at Elite Tree Care to discuss changing the standard fertilizer solution to better serve your tree.