Keeping your trees and shrubs healthy requires the perfect combination of sunlight, water, nutrients, and pruning. While these certainly contribute to their vitality, there is another secret weapon that most homeowners and gardeners might not know about: plant growth regulators. These compounds, designed to regulate plant growth, can improve the growth, health, and appearance of your trees and shrubs. In this blog post, we’re going to look at the benefits of growth regulators, which trees and shrubs benefit most from them, and how often you should treat them!

What are tree and shrub growth regulators?

Plant Growth Regulators (PRGs) are products designed to alter plant growth and development. PRGs can either promote or inhibit plant growth, development, and fruiting. Certain PRGs can also help plants tolerate stress and disease. PRGs can be applied in a variety of methods, including foliar sprays, soil drenches, injections, and granules. While PRGs can be an excellent tool to improve plant health, they should be applied by a certified arborist, as overdosing can be dangerous to the plant.

1. Encroaching: Large trees or shrubs planted too close to buildings and power lines will start encroaching on these structures and can cause some hefty damage.
2. Falling: Larger, fast-growing trees such as tulip poplars, red maples, and silver maples, often grow too fast and aren’t able to establish robust root systems. This can lead to them uprooting and falling during storms and high winds.
3. Health Problems: Large plants need large amounts of water, minerals, and soil space. If the tree or shrubs is planted in a small area, an area that doesn’t receive lots of water, or soil that isn’t nutrient-rich it will not be able to support itself. Large plants in these situations will suffer from heat stress, diseases, and insect infestations which can be costly to fix.

When dealing with the situations above it becomes necessary to limit the size and volume of your tree. In the past, tree size and volume have been limited through trimming trees frequently but this can be costly and time-consuming. Thankfully, there is another way to control your tree’s size and volume – Tree Growth Regulators.

What are the benefits of growth regulators?

Growth Reduction

As the name indicates, the biggest benefit of Tree Growth Regulators is a reduction in the tree’s yearly growth. A single application of Tree Growth Regulator can reduce new growth by 90%. This means if your tree commonly grows a few feet every year that growth would be reduced to a few inches with the Tree Growth Regulator.

This will allow your trees to flourish without growing into power lines, damaging your roof, or encroaching on other structures.

Root & Leaf Enhancement (Better Root System & Greener Leaves)

As a result of reducing canopy growth, your tree or shrubs can now focus its time and energy on enhancing its leaf appearance and root growth. Our Plant Growth Regulator will stimulate the production and development of fine roots which will allow the tree or shrub to absorb more water and minerals.

The application also results in increased chlorophyll production leading to deep green leaves that are able to capture more energy from the sun. As a result of these enhancements, your plant will be better equipped to recover from stress and damage.

Stress, Drought, Disease & Insect Protection

Quickly recovering from stress and damage will help your trees stay healthy. Growth Regulators don’t stop there; they also increase your tree’s resistance to tree diseases and insect infestations.

On top of that Tree Growth Regulators provide your tree with increased drought resistance. They do this by increasing the density of fine roots which absorb water and by reducing the amount of water required to support the tree.

Which trees and Shrubs benefit most from growth regulators?

Some trees that do benefit from PGRs are fruit trees, large evergreen trees, and maple trees. Shrubs that benefit greatly from growth regulators include boxwood shrubs, rose bushes, and Azalea. Growth regulators maintain the appropriate size of these plants and promote dense foliage. As a result, they remain attractive with a longer lifespan. On the contrary, PGRs are not suitable for all plant types. According to our Certified Arborists some trees such as Japanese maples and Dogwoods, do not benefit from tree growth regulators. If you have plants that are suffering from the following conditions, then a Growth Regulator may be a good choice for your landscape.

>> Your tree or shrub is growing in a limited, urban, high-traffic area.

• Limited CRZ: When a big tree is surrounded by other structures such as sidewalks or driveways, the vital root system cannot provide enough water and nutrients.
  • Growth Regulators help plants handle these challenges.

• Tough Growing Locations: When trees or shrubs are planted in tight areas (ex, sidewalks or parking lots), a heat island is created. This leads to a common symptom called leaf scorch.
  • Growth Regulators reduce the plant’s need for water, making them easier to maintain without sacrificing the health of their leaves.

• Compacted Soil: Due to heavy traffic and constant construction, soil compaction has become a common issue in urban settings. It is nicknamed the “Silent Killer” of trees. This nickname comes from the damage soil compaction leaves behind in the crucial root system which can eventually kill the tree altogether.
  • Growth Regulators can stimulate root growth and help the plant more effectively handle nutrient and water intake.

>> Your tree or shrub needs to get trimmed more often than you would like.

• Mature Plants: A common complaint our Certified Arborists hear is how clients’ trees or shrubs crowd into essential structures such as their gutters, roofs, or neighbors’ yards – all of which lead to the need for constant tree trimming.
  • Growth Regulators slow growth which can help reduce the frequent need for tree trimming. With help from PGRs, trees can go years without trimming.

• Manicured Looks: Homeowners may want their plants to look a certain way for aesthetic reasons.
  • Growth Regulators maintain the aesthetic for a longer amount of time.

>> Your plant is slowly starting to decline.

Have you been noticing any of the following symptoms of decline?

• Branch dieback
• Browning and yellowing leaves
• Thinning canopy

Growth Regulators support tree and shrub health and can aid in recovery from these symptoms.

How often do trees and shrubs need treatment?

Plant Growth Regulators are applied once every 3 years. Over the years they will provide growth reduction, root & leaf enhancement, and help with disease & insect protection.

Protect your plants’ long-term health with RTEC

Plant growth regulators are a valuable tool for keeping trees and shrubs healthy and attractive. They improve plant health and save you time and energy! Moreover, they can improve tree growth, promote the health and vigor of shrubs and help plants respond to stress. If you want to protect your plants’ long-term health, contact a certified arborist today for help in implementing a growth regulator regimen, like RTEC.

The best thing you can do for your plants is to enroll in a comprehensive year-round program, like our Canopy Protection Program.