A plant growth regulator (PGR) might sound technical, but it’s actually one of the best tools we have to help Colorado trees thrive in tough urban conditions. A plant growth regulator is a professional-grade treatment that gently slows a tree’s canopy growth over a 2–3 year period. This slowdown gives trees the chance to focus their energy below ground—building stronger roots and increasing resilience against drought, disease, and other stressors common in our state.
Why would I want to slow my tree’s growth?
While it might seem counterintuitive, slowing a tree’s growth comes with big benefits—especially in urban or stressed environments. When canopy growth slows down, your tree can redirect more energy to developing fine roots. These roots are key for absorbing water and nutrients, which improves drought tolerance and overall vitality.
In short: a slower-growing tree can actually be a stronger, healthier tree.
What are some of the benefits of PGR treatment?
Healthier roots – Promotes more fine root growth for better water and nutrient absorption
Greener leaves – Boosts chlorophyll production, especially helpful for mildly chlorotic trees
Stronger structure – Increases stress tolerance and resilience to drought, heat, and disease
When is PGR a good option?
PGR is an excellent option for:
- Trees growing near homes, patios, or overhead lines
- Trees impacted by construction or restricted root zones
- Landscapes where soil is compacted or space is tight
Is this treatment safe for my tree?
Yes. When applied by a trained arborist, PGR is a safe and effective way to support tree health. It works gradually over time and does not harm the tree—in fact, it often helps trees perform better in the dry, and sometimes harsh, conditions we see along the Front Range.
Our certified arborists can evaluate your tree and recommend a custom care plan.
