Why Your Trees Are Starving: The Hidden Truth About Surface Fertilizers in Suffolk County’s Sandy Soils

Long Island homeowners know the struggle: despite regular fertilization, their trees remain lackluster, with yellowing leaves, stunted growth, and poor resistance to disease and pests. The problem isn’t the amount of fertilizer being applied—it’s where it’s going. Suffolk County fertilizers are responsible for approximately 50% of the total nitrogen loads to groundwater in the Peconic Estuary, yet many trees continue to show signs of nutrient deficiency. This paradox reveals a fundamental flaw in traditional surface fertilization methods.

The Suffolk County Soil Challenge

Suffolk County’s unique geological composition creates specific challenges for tree nutrition. Suffolk County hosts a great diversity of agriculture and the high value of land and the maritime climate creates much different conditions for agricultural production than the rest of NYS. The predominant sandy soils that characterize much of Long Island are highly permeable, causing surface-applied fertilizers to leach away before tree roots can effectively absorb them.

Sandy soils in Minnesota are also more prone to nutrient losses through leaching, as water carries nutrients such as nitrogen, potassium or sulfur below the root zone where plants can no longer access them. This same principle applies to Suffolk County’s sandy conditions, where fertilizer not absorbed by grass leaches into the subsoil and makes its way into groundwater or runs off into surface water.

Why Surface Fertilizers Fail Trees

Traditional broadcast fertilization methods work adequately for shallow-rooted plants like grass, but they fall short for trees with extensive root systems. While surface fertilization might be beneficial for grass and smaller landscape plants, trees that have deep-reaching roots can’t be effectively fertilized from the surface. The fundamental issue lies in the mismatch between where nutrients are placed and where tree roots actually absorb them.

Most fibrous absorbing tree roots are found in the top 2-8″ of soil where water and oxygen are abundant, yet surface fertilizers often don’t penetrate effectively to this critical zone, especially in compacted urban soils. One of the primary advantages of fertilization is its ability to bypass surface-level issues such as compacted soil or competing vegetation. Traditional fertilization methods often result in limited nutrient uptake due to soil compaction or shallow root systems.

The Deep Root Fertilization Solution

Deep root fertilization addresses these challenges by delivering nutrients directly to the tree’s active root zone. This treatment uses high-pressure professional equipment to inject a blend of nutrients and organic matter into the soil around your trees’ roots. The liquid fertilizer is injected to a depth of roughly 5 inches (this is where most of a tree’s feeder roots are found).

This targeted approach offers several advantages over surface methods. This method of fertilization is more beneficial than surface feeding as it takes the nutrients to the roots without needing to wait for irrigation or precipitation to move the fertilizer into the root zone. Additionally, because nutrients are applied throughout the root zone, rather than on the soil surface, deep root fertilization greatly decreases the risk of fertilizer runoff.

Environmental Benefits for Suffolk County

Given Suffolk County’s environmental concerns about nitrogen pollution, deep root fertilization offers a more environmentally responsible approach. Moreover, deep-root fertilization is an environmentally friendly practice. It minimizes nutrient runoff and leaching, reducing the risk of water pollution and environmental damage compared to surface fertilization methods.

This is particularly important in Suffolk County, where in 2006, 15 community public water supply wells, and nearly 10% of private wells in Suffolk County, were found to violate the 10 mg/l maximum contaminant level (MCL) set for nitrates to ensure safe drinking water.

Professional Application Makes the Difference

The effectiveness of deep root fertilization depends heavily on proper application by trained professionals. To ensure that all parts of the root zone receive enough nutrients, we usually inject in a grid pattern throughout the entire area under the tree canopy (out to the dripline, or canopy edge) and sometimes even beyond.

Companies like Jones Tree & Plant Care understand these local challenges intimately. Jones Tree & Plant Care offers professional tree and plant services in Suffolk County, NY. As a licensed arborist, Jones is committed to offering scientifically based landscape management and delivering quality services. Jones Tree and Plant Care will inspect your landscape, diagnose any problems, and make recommendations based on knowledge and expertise gained through over 10 years of experience in the industry.

Their approach emphasizes customized care: Jones Tree and Plant Care creates specific programs based on the needs of each individual customer and property. A total tree and plant care approach will improve growth, condition and appearance of your property, all while using environmentally sensitive, affordable treatments.

Timing and Long-Term Benefits

Proper timing enhances the effectiveness of deep root fertilization. Although deep root fertilization treatments can be applied in spring and summer, they’re more typically done in early fall. This gives the tree time to absorb the necessary nutrients before winter arrives and while the tree isn’t stressed by excessive heat, lack of moisture, and active growth.

The investment in professional Deep Root Fertilization in Suffolk County, NY pays dividends in tree health and longevity. Just one deep root fertilizer treatment will provide significant, long-lasting results for your trees, while also contributing to improved soil structure through deep root fertilization also improves soil aeration, letting the tree more easily absorb essential nutrients, water, and oxygen—everything the tree needs to survive.

The Bottom Line

For Suffolk County property owners struggling with declining tree health despite regular fertilization efforts, the solution may not be more fertilizer—it’s better fertilizer placement. Deep root fertilization represents a paradigm shift from the wasteful surface broadcasting methods that have dominated landscape care for decades. By working with certified arborists who understand both the science of tree nutrition and the unique challenges of Long Island’s soil conditions, homeowners can achieve healthier trees while protecting the region’s precious water resources.

The choice between surface and deep root fertilization isn’t just about tree health—it’s about environmental stewardship and long-term landscape sustainability. In Suffolk County’s delicate ecosystem, feeding trees from below isn’t just more effective; it’s the responsible choice for both your landscape and your community’s future.