fertilization, mulching and root collar excavation

Fertilization, Mulching & Root Collar Excavation

Proper tree fertilization and mulching is key in fostering a healthy landscape and lawn. 

The quality of the soil around a tree’s roots determines the health of the tree. Trees require nutrients to live and thrive. When one or more of these nutrients are deficient in the soil, the tree will not reach its full landscape potential, will be more susceptible to disease and insect problems, and will have a shorter life than a similar, well-fertilized tree. For this reason, proper tree fertilization is key.

Tree Fertilization

fertilization and mulchingProper fertilization is one tool arborists use to restore soil fertility and help to reach the goal of a healthy tree root system. Red Cedar Arborists base recommendations for tree nutrition on soil analysis data. 

Trees in urban and suburban environments are often:

  • Under high-stress conditions due to low moisture availability
  • Have compacted soil
  • Are physically damaged
  • Stressed from nearby construction
  • Forced to compete with turf and nearby trees and shrubs

Fertilizer applications may reduce, but cannot eliminate, environmental stresses such as these. It is important to keep newly planted trees watered and pruned and to keep weeds away from their bases to avoid excess stress. The best indicator of whether fertilization is necessary is a soil test. Ideally, a soil sample should be taken every 3 to 5 years to determine whether any nutrients are lacking. Red Cedar can provide you with a free consultation and a soil analysis to see what is actually needed for your specific plant.


Mulches are materials placed over the soil surface to maintain moisture and improve soil conditions. Mulching is one of the most beneficial things a homeowner can do for the health of a tree. Mulch can reduce water loss from the soil, minimize weed competition, and improve soil structure. Properly applied, mulch can give landscapes a handsome, well-groomed appearance.

Trees growing in a natural forest environment:

  • have roots anchored in a rich, well-aerated soil full of essential nutrients
  • The soil is blanketed by leaves and organic materials that replenish nutrients and provide an optimal environment for root growth and mineral uptake.

fertilization for urban treesTrees growing in urban landscapes typically deal with much harsher environments with:

  • Poor soils
  • Little organic matter
  • Large fluctuations in temperature and moisture

Applying a 2- to 4-inch layer of organic mulch can mimic a more natural environment and improve plant health.

Mulch must be applied properly; if it is too deep or if the wrong material is used, it can actually cause significant harm to trees and other landscape plants.

Root Collar (Lower Stem) Care/ Root Collar Excavation

Root collar excavation or the removal of soil and mulch from against the trunk, is a simple, effective process that can correct deep planting and over-mulching. Can you see the root flare of your trees? This is the low portion of the trunk where it flares out into the roots. If a tree has symptoms of stress, such as reduced twig and leaf growth, off-color leaves, a thin crown, or die back, deep roots may be the problem if it lacks a well-developed root flare.

What can be done? Short of raising the tree by transplanting, root collar excavation is the only option available to treat an established tree with deep roots. Removing the soil from around the base of the tree provides better aeration to the soil and roots. Typically, soil is removed just wide enough to expose the root flare and create a slope that will keep the soil from falling back into the excavation. Air excavation tools are fast and minimize damage to roots. Red Cedar Arborists report good success revitalizing trees with root collar excavations

If you are looking to have a soil test done, for some help with proper mulching and fertilization, or you suspect your tree may need a root collar excavation, contact Red Cedar today for your free consultation!