DEEP ROOT FERTILIZATION

All plants need a sufficient supply of nutrients to remain healthy and put on new growth. Most trees in a forested setting can utilize the decaying fallen leaves and branches from the surrounding trees as a source of nutrients. As the leaves and twigs decompose, they break down into a nutrient-rich energy source for the tree. Urban trees aren’t so lucky. Most city trees are surrounded by concrete or asphalt. The root system is covered up by hard surfaces and therefore is cut off from receiving the needed nutrient (and water) required for healthy growth. Suburban trees are usually surrounded by turf—which has a thick layer of roots that will absorb most water and nutrients placed on the surface before any tree roots get a chance to benefit from them. Unlike forested areas where the leaves are left to decompose on top of the ground, the trees in most suburban areas are robbed of that benefit. Most homeowners rake up the leaves from the trees in order to keep the turf healthy, thereby robbing the trees of much-needed, natural nutrients.

WHAT IS FERTILIZATION?

Fertilization is the introduction of material (organic or synthetic) into a tree to provide nutrients and other material to the tree. Fertilizers come in many forms: granular, liquid, pellets, and concentrates (usually used in systemic trunk injections). The materials used in fertilization will supplement the missing nutrients that an urban tree will suffer from due to the lack of organic material available via natural forms.

CAN I FERTILIZE MY OWN TREES?

When it comes to fertilizing trees and shrubs Ulrich Tree Care recommends deep root fertilization. Deep root fertilization introduces needed nutrients into the root zone of the tree (below the turf roots), allowing the nutrients to be absorbed and utilized by the tree roots in a usable form. Some homeowners will spread granular fertilizer over the root system of a tree and water it in, but most of the material will be absorbed by the turf roots - and top spread granular fertilizer won’t have the long-lasting effect of a deep root application. At Ulrich Tree Care, we used products formulated specifically for trees and utilized professional, high-pressure equipment to inject the material below the turf roots—allowing the product to be absorbed directly into the tree roots and not by the turf.

HOW OFTEN SHOULD MY TREES BE FERTILIZED?

At Ulrich Tree Care we recommend that most standard residential trees be fertilized once per season. If the trees are in an area where the leaves can be left to decompose and provide nutrients for themselves, we usually don’t recommend fertilizing. Alternatively, if a tree is in a high-stress location, or is suffering from some other insect, disease, or abiotic issue we may recommend that the tree be fertilized in the Spring and in the Fall.

WHAT TYPE OF FERTILIZER DO MY TREES NEED?

We always use different fertilizer formulations for different growing seasons. In the Spring we will usually use a formulation that is higher in Nitrogen (a nutrient most associated with leaf/shoot growth) such as 27-9-9. Conversely, in the Fall we will use a formulation lower in Nitrogen (since the tree won’t need to be supporting leaf growth) but higher in Potassium (which is the major nutrient most associated with strong root growth). At Ulrich Tree Care we are experienced and educated in diagnosing and recommending proper fertilization types and techniques to keep your trees and shrubs growing at their peak.