Great Western Tree Care arborist injecting fertilizer into the root zone beside a mature tree trunk
Tree & Plant Health

Tree Fertilization

Custom tree fertilization programs designed around the soil, species and growing conditions of Colorado's Front Range.

Great Western Tree Care develops targeted fertilization programs based on tree health, soil conditions and species-specific nutrient requirements — not one-size-fits-all seasonal applications.

Serving Colorado's Front Range · (720) 535-8769

Science-Based Tree Nutrition

Healthy Trees Start Below the Surface

Colorado trees live in conditions very different from those found in their native environments. Along the Front Range, alkaline clay soils, limited precipitation, compacted landscapes and competition from turf and surrounding development can make essential nutrients difficult for trees to access.

Fertilization should therefore begin with understanding the tree and the soil — not simply applying fertilizer.

Great Western Tree Care develops targeted fertilization programs based on soil conditions, tree species, visible health symptoms and long-term landscape goals.

When appropriate, laboratory soil analysis helps identify macronutrient and micronutrient availability, soil pH, organic matter and other conditions affecting tree health.

Combined with proper supplemental watering and proactive plant-health management, fertilization can become an important component of long-term tree care.

Healthy, well-nourished ornamental tree in full spring bloom on a Colorado Front Range property

Why Fertilization Matters

  1. 01

    Nutrient-Poor Soils

    Many Colorado landscapes contain shallow, rocky, compacted or nutrient-depleted soils that may not provide adequate nutrients for established trees and shrubs.

  2. 02

    Water Stress

    Colorado's semi-arid climate and variable precipitation can reduce a tree's ability to absorb available nutrients from the surrounding soil.

  3. 03

    Competition

    Trees in urban and suburban landscapes compete with turf, surrounding plants, pavement and development for available water and nutrients.

  4. 04

    Growth & Resilience

    Strategic fertilization can support root development, healthy growth, stress tolerance and overall plant vigor when nutrient deficiencies or soil conditions warrant treatment.

  5. 05

    Appearance

    Proper nutrient availability contributes to healthy foliage, flowering and the overall appearance of trees and shrubs.

Understanding the Root Zone

Colorado Soil Changes the Equation

Effective fertilization begins by understanding what the soil contains — and what the tree can actually access.

Laboratory Soil Testing

When appropriate, soil samples can be collected from within the root zone and submitted for laboratory analysis.

Testing can evaluate factors including:

  • Nitrogen
  • Phosphorus
  • Potassium
  • Iron
  • Manganese
  • Zinc
  • Boron
  • Soil pH
  • Organic matter
  • Cation exchange capacity

The objective is to develop a treatment recommendation based on actual site conditions rather than guesswork.

Soil pH & Nutrient Availability

Alkaline soil conditions common across the Denver metro area can make nutrients such as iron and manganese difficult for tree roots to access even when those nutrients are physically present in the soil.

One common result is iron chlorosis, often recognized by yellow foliage with contrasting green veins.

Where appropriate, soil amendments or targeted nutrient treatments may be incorporated into the overall tree-health program.

Organic Matter & Soil Biology

Organic matter contributes to moisture retention, nutrient cycling and healthy soil biology.

Where conditions warrant it, Great Western may recommend strategies such as compost topdressing or other soil amendments designed to improve root-zone conditions over time.

Tree & Plant Health

A Program Built Around the Tree

01

Deep Root Fertilization

Deep-root fertilization delivers liquid nutrient solutions into the tree's root zone rather than relying exclusively on material applied at the soil surface.

Treatment programs can be adjusted based on tree species, size, health condition and soil characteristics.

02

Micronutrient Management

Some Colorado trees experience deficiencies involving iron, manganese, zinc or other micronutrients.

When appropriate, targeted nutrient treatments can be incorporated into the overall plant-health program based on symptoms, species and site conditions.

03

Iron Chlorosis Treatment

Yellow foliage with green veins can indicate iron chlorosis, a common issue in trees growing in alkaline Front Range soils.

Treatment strategy depends on the tree, severity of symptoms and underlying soil conditions.

04

Soil Amendment

Where root-zone conditions contribute to poor tree health, fertilization may be combined with soil-management strategies designed to improve nutrient availability, moisture retention and overall soil conditions.

05

Seasonal Programs

Tree nutrient needs change throughout the growing season.

Great Western develops treatment schedules based on tree health, environmental conditions and appropriate seasonal timing rather than automatically applying the same treatment year-round.

Technical Feature

How Deep Root Fertilization Works

Deep-root fertilization introduces liquid nutrients directly into the active root zone using specialized injection equipment.

This approach allows nutrients to reach areas where absorbing roots are concentrated while reducing reliance on surface-applied fertilizer moving through compacted soil.

The nutrient formulation and application strategy can be adjusted based on soil-test results, tree species and observed deficiencies.

Slow-Release vs. Fast-Release

Great Western generally favors controlled nutrient delivery designed to support steady uptake rather than creating an unnecessary surge of growth.

Faster-release components may be incorporated when specific deficiencies or conditions warrant a more immediate response.

Micronutrients

Colorado trees may also require supplemental micronutrients.

Chelated nutrient formulations can be useful where alkaline soil conditions limit nutrient availability.

The appropriate treatment depends on tree species, symptoms and site conditions.

Timing Matters

Spring
Applications may be scheduled as soil conditions warm and active root growth resumes.
Fall
Appropriate fall treatments can support root development and nutrient reserves heading into dormancy.

Great Western avoids treating trees simply because a calendar says it is time. Extreme heat, drought stress and other environmental conditions may change when or whether fertilization is appropriate.

Tree Fertilization by Property Type

Established Trees

Mature shade and ornamental trees can experience nutrient stress after years of competing with turf and surrounding landscapes for available soil resources.

Reduced canopy density, smaller foliage, premature color change or other symptoms may indicate the need for a broader tree-health evaluation.

Young & Newly Planted Trees

Young trees require appropriate watering, root development and soil conditions during establishment.

Nutrient management should complement — not replace — proper planting and establishment care.

Trees Showing Chlorosis

Iron chlorosis is common among tree species sensitive to alkaline Front Range soils.

Properties with recurring chlorosis may require an ongoing strategy combining nutrient management, soil improvement and monitoring rather than a single application.

How We Work

Diagnose first. Treat second.

  1. 01

    On-Site Tree & Soil Assessment

    We evaluate tree species, visible health symptoms, soil conditions and the surrounding landscape. When appropriate, soil samples may be collected for laboratory analysis.

  2. 02

    Nutrient Prescription

    Based on tree condition and available soil information, we develop a treatment plan specifying the appropriate nutrient strategy, application method and timing.

  3. 03

    Scheduling & Preparation

    Treatment is scheduled around appropriate seasonal and environmental conditions. Watering and other plant-health considerations may also be coordinated with the treatment plan.

  4. 04

    Application

    Our crew applies the prescribed treatment using professional equipment appropriate to the tree and property.

  5. 05

    Monitoring & Follow-Up

    Tree response can be evaluated over subsequent visits and future treatment recommendations adjusted based on observed results.

Investment

What Does Tree Fertilization Cost?

Pricing depends on the number of trees, soil conditions, treatment type and scope.

Soil Testingper property
$75–$200
Deep Root Fertilizationper tree / application
$100–$300
Iron Chlorosis Treatmentper tree
$150–$400
Seasonal Programannually for properties with approximately 5–10 trees
$300–$800
Comprehensive Soil Amendment Programdepending on scope
$500–$2,000+

Actual cost depends on factors including

  • Number of trees
  • Tree size
  • Soil-testing requirements
  • Treatment type
  • Nutrient formulation
  • Site access
  • Existing soil conditions
  • Scope and frequency of treatment
Request an Estimate
Expertise Matters

Tree Health Requires More Than Fertilizer

ISA-Certified Arborists
3ISA-Certified Arborists
Colorado Department of Agriculture Plant Health Care Qualified Supervisors
3Colorado Department of Agriculture Plant Health Care Qualified Supervisors
TRAQ-Certified Professionals
2TRAQ-Certified Professionals
Certified Treecare Safety Professional
1Certified Treecare Safety Professional
Since 2018
Family-OwnedSince 2018

Great Western's fertilization programs are developed within a broader arboriculture and plant-health framework. The objective is to determine what the tree actually needs — and whether fertilization is even the appropriate treatment.

The Great Western Tree Care team with their branded trucks and bucket truck in Larkspur, Colorado
Common Questions

Tree Fertilization FAQ

When is the best time to fertilize trees in Denver?

Early spring and early fall are commonly appropriate fertilization windows for Front Range trees. Spring treatments can support active growth, while appropriate fall applications can support root development and nutrient reserves. Extreme summer heat and active drought stress may make fertilization inappropriate until conditions improve.

Why are my tree leaves turning yellow with green veins?

Yellow foliage with contrasting green veins is commonly associated with interveinal chlorosis. In Colorado landscapes, alkaline soil conditions can make iron unavailable to susceptible tree species even when iron exists within the soil. A professional evaluation can help determine whether iron deficiency or another condition is responsible.

How often should trees be fertilized in Colorado?

There is no single schedule appropriate for every tree. Treatment frequency depends on tree species, age, health, soil conditions, nutrient deficiencies and environmental stress. Soil testing and ongoing tree-health evaluation can help determine whether continued treatment is necessary.

Is deep root fertilization better than granular fertilizer?

Deep-root fertilization allows nutrients to be delivered directly into the active root zone. This can be particularly useful in landscapes with compacted or challenging soil conditions. The appropriate application method ultimately depends on the tree and site.

Can fertilization save a tree that is already declining?

Sometimes — but fertilization is not a cure-all. Decline can result from nutrient deficiency, drought, root problems, pests, disease, structural issues or combinations of several factors. Great Western evaluates the tree first to determine whether fertilization is likely to help or whether another intervention is more appropriate.

Do you fertilize every tree species the same way?

No. Different species have different nutrient requirements, sensitivities and root characteristics. Treatment recommendations should account for tree species, size, health, soil conditions and observed deficiencies.

Colorado's Front Range

Tree Fertilization Across the Greater Denver Area

Great Western Tree Care provides tree fertilization and plant-health services throughout Douglas County, the Denver Metro, and surrounding Front Range communities.

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Nick Anderson, a Great Western Tree Care arborist, on a Colorado property
Nick Anderson, Sales Manager, Great Western Tree Care
Free Estimate

Healthy trees start with healthy soil.

Great Western Tree Care develops science-based fertilization programs around the specific needs of your trees and property. Schedule a free on-site tree health evaluation and we'll help determine the right next step.

(720) 535-8769

Serving Colorado’s Front Range