How to kill cherry tree root suckers

Cherry trees, while beautiful and fruit-bearing, often present a common challenge for gardeners: the emergence of root suckers. These unwanted shoots, springing from the rootstock below the graft union, can quickly become a nuisance. Not only do they detract from your tree’s aesthetic appeal, but more importantly, they compete with the main tree for vital nutrients and water, potentially weakening its growth and fruit production. Understanding why these suckers appear and, more importantly, how to effectively eliminate them is crucial for maintaining a healthy and productive cherry tree. This article will guide you through various strategies, from preventive measures to mechanical and chemical controls, ensuring your cherry tree remains vibrant and sucker-free.

Understanding cherry tree root suckers and why they emerge

Root suckers are vigorous shoots that sprout directly from the root system or the base of a tree, particularly below the graft union. In the case of cherry trees, these suckers originate from the rootstock, the hardy root system onto which the desired cherry variety (the scion) has been grafted. They are essentially a reversion to the rootstock’s natural growth habit. The primary reason cherry trees, and many other grafted fruit trees, produce suckers is often due to stress. This stress can manifest in several ways:

Pruning shock: Aggressive pruning of the canopy can send a signal to the root system to compensate by pushing out new growth.
Root damage: Injury to the roots from digging, tilling, or even lawnmowers can stimulate dormant buds on the rootstock to activate.
Environmental stress: Drought, nutrient deficiency, or extreme temperature fluctuations can weaken the main tree, encouraging the rootstock to assert itself.
Inherent vigor of the rootstock: Some rootstocks are naturally more prone to suckering than others, making continuous management necessary.

The impact of suckers on your main cherry tree is significant. They act as parasitic growths, diverting essential water and nutrients that should be feeding the fruiting branches. This competition can lead to reduced fruit yield, smaller fruit size, and a general decline in the tree’s vigor and overall health. Furthermore, suckers can provide entry points for pests and diseases, jeopardizing the entire tree.

Initial steps and mechanical removal strategies

Effective management of cherry tree root suckers often begins with diligent observation and precise mechanical removal. Early detection is key to preventing a small problem from becoming an overwhelming one. The moment you spot a sucker, take action.

The most crucial aspect of mechanical removal is understanding that simply cutting suckers at ground level is rarely a permanent solution; it often stimulates more vigorous regrowth. Instead, aim to remove them at their point of origin:

Pruning techniques: For suckers emerging from the soil, carefully dig away the surrounding soil to expose the base of the sucker where it connects to the root. Using sharp, clean pruning shears or a knife, make a clean cut as close to the root as possible, ensuring no stub is left behind. This minimizes the chance of regrowth. For suckers growing from the base of the trunk below the graft union, cut them flush with the trunk.
Regular monitoring: Make it a habit to inspect your cherry tree regularly, especially during periods of active growth. The sooner you remove suckers, the less energy they will have diverted from the main tree.
Physical barriers: While often used during new plantings, root barriers can be an effective preventative measure. These are typically sheets of rigid plastic or metal installed vertically in the soil around the root zone to physically block roots from sending up suckers in unwanted areas. When installing, ensure they are deep enough to be effective without girdling the main tree’s roots.
Mulching: A thick layer of organic mulch (3-4 inches deep) around the base of the tree can help suppress the emergence of new suckers by blocking sunlight and making it harder for shoots to push through. However, highly determined suckers may still find their way through, so this should be combined with other methods.

Mechanical removal, when done correctly and consistently, is often the safest and most environmentally friendly approach, especially for minor sucker issues.

Chemical control methods for persistent suckers

When mechanical removal proves insufficient, or if you’re dealing with a particularly persistent or widespread sucker problem, chemical control methods can offer a more definitive solution. It’s imperative to exercise extreme caution when using herbicides around valuable trees to avoid damaging the main cherry tree.

The goal with chemical control is to apply a systemic herbicide that will be absorbed by the sucker and translocated down into the root system, killing the root tissue that is generating the shoots. Two common types of herbicides used are glyphosate and triclopyr.

Glyphosate-based herbicides: These are non-selective, meaning they will kill any plant tissue they come into contact with. They are very effective at killing root systems.
Triclopyr-based herbicides: Often more selective for broadleaf plants and woody brush, triclopyr can also be very effective on woody suckers.

The most effective application method for suckers is the cut-stump method:

Cut the sucker as close to the ground or its origin point as possible, creating a fresh wound.
Immediately (within minutes) apply a concentrated herbicide solution directly to the fresh cut surface using a paintbrush or a dedicated herbicide applicator. This direct application minimizes drift and contact with desirable vegetation.

Foliar spray application on suckers is generally less effective for killing the root system and carries a much higher risk of herbicide drift, potentially damaging the main cherry tree or nearby plants. If attempting foliar spray, use a very low concentration specifically designed for brush and weed control, and only on calm, non-windy days, shielding the main tree if necessary.

Herbicide application considerations

Herbicide Type	Application Method	Target	Risk to Main Tree	Notes
Glyphosate (concentrated)	Cut-stump	Root system of suckers	Low (if precise)	Non-selective; very effective when applied to fresh cuts.
Triclopyr (concentrated)	Cut-stump	Root system of suckers	Low (if precise)	Good for woody plants; often found in brush killers.
Glyphosate (diluted)	Foliar spray (avoid)	Leaves of suckers	Moderate to High (drift)	Less effective for root kill; high risk to main tree.

Always wear appropriate personal protective equipment (PPE) such as gloves and eye protection when handling herbicides. Read and strictly follow the manufacturer’s instructions for mixing ratios, application rates, and safety precautions. Over-application can lead to damage to the main tree, even with precise cut-stump methods, as the chemicals can sometimes be absorbed and translocated to undesirable areas of the root system.

Long-term prevention and cultural practices

Preventing root suckers from appearing in the first place is the most sustainable strategy for a healthy cherry tree. A combination of good cultural practices and informed choices can significantly reduce their incidence.

Proper planting: When planting a new cherry tree, ensure the graft union (the swollen area where the scion meets the rootstock) is always positioned several inches above the soil line. If the graft union is buried, the scion itself may begin to root, or the rootstock is more likely to send up suckers.
Choosing the right rootstock: Some cherry tree rootstocks are known to be less prone to suckering than others. If you have the option, inquire about “non-suckering” or “low-suckering” rootstock varieties when purchasing a tree from a reputable nursery.
Stress reduction: A healthy, unstressed cherry tree is less likely to produce suckers.

Adequate watering: Ensure your tree receives sufficient water, especially during dry spells. Deep, infrequent watering is generally better than shallow, frequent watering.
Proper fertilization: Provide balanced nutrients based on soil tests. Avoid excessive nitrogen, which can encourage leafy growth at the expense of fruit and potentially stimulate suckers.
Protecting roots from damage: Be mindful when mowing or tilling around the base of the tree. Even minor nicks to the root system can trigger sucker growth. Consider creating a mulch ring around the tree to keep mowers and trimmers at a safe distance.

Pruning the main tree correctly: Avoid over-pruning the main canopy, as severe cuts can stress the tree and inadvertently promote sucker development. Practice proper structural pruning to maintain good tree health and vigor.
Regular monitoring and immediate removal: Even with the best preventative measures, a few suckers may still emerge. Make a habit of regularly inspecting your tree and removing any new suckers as soon as they appear, before they have a chance to grow large and establish a strong connection to the root system.

By implementing these long-term strategies, you can minimize the effort required for sucker control and promote a more robust, fruit-producing cherry tree.

Managing cherry tree root suckers requires a combination of understanding, vigilance, and appropriate action. We’ve explored why these unwanted shoots appear, their detrimental effects on your cherry tree, and a range of effective strategies to combat them. From precise mechanical removal techniques—such as digging down to the sucker’s origin and making a clean cut—to targeted chemical applications using the cut-stump method with herbicides like glyphosate or triclopyr, you now have a comprehensive toolkit. Furthermore, we highlighted the critical importance of long-term preventative measures, including proper planting depth, choosing low-suckering rootstocks, and maintaining overall tree health through correct watering, fertilization, and careful pruning. Ultimately, success lies in a consistent, multi-faceted approach. By combining these methods, you can effectively kill existing suckers, prevent future outbreaks, and ensure your cherry tree remains a healthy, productive, and aesthetically pleasing asset to your garden for years to come.

Image by: Igor Omilaev