Every landscaper has faced that situation where, no matter how much tending, pruning or fertilizing you do, the plants and grass just don’t seem to thrive. That may mean it’s time to look beneath the surface – in the soil.
Amendments are often necessary to correct an imbalance or offset a structural problem in the soil. These organic or nonorganic substances are tilled several inches into the topsoil, unlike mulches or top dressings which are left on the surface. Amendments release nutrients and aerate the soil, supporting an ideal growing environment. Understanding the soil you’re working with and addressing its needs can help to cultivate that flourishing landscape your customers crave.
Diagnosing the problem.
Sometimes a problem with the soil has visible symptoms: excess weed or moss, lingering puddles or standing water, recurring salt stains, or areas that remain dry and parched regardless of watering. Or, you may notice that despite routine fertilization, there’s little response.
“Soil is composed of many different living organisms that work to provide nutrients to the plants that it supports,” says Jerry Schill, CEO and co-owner of Schill Grounds Management in North Ridgeville, Ohio. “It's always best to test your soil to determine exactly what it needs. Just like you shouldn't switch and swap medications with friends, soil amendments are not a one-size-fits-all solution.”
The test will indicate if there is an imbalance in nutrients, which you can then address with a more targeted additive. Schill says there are other factors to take into consideration with the test results.
One is knowing what a property will be used for. “For instance, agricultural properties that have a lot of heavy equipment running on them are more likely to experience compaction. In these situations, you might want to add sand and leaf compost to alleviate that problem,” he says.
Also, it’s important to know what your client is planning to grow and understand the environment in which those plants thrive. “If you're using a lot of hydrangeas and azaleas, for example, you might need an alkaline amendment rather than one that's more acidic.”
Once you have all the pieces of the puzzle, you can then take steps toward addressing the problem.
Common chemical imbalances.
A pH imbalance is one of the most frequent reasons for a lackluster lawn, and this is something your soil test will reveal.
“If the pH is too low, you’ll see an off-color appearance and the inability of the lawn to properly respond to a fertilizer application,” says Greg Adams, president of One Step Tree & Lawn Care in Rochester, New York.
A pH reading of 7.0 is generally desirable and considered neutral. A pH of 0 to 7.0 means the soil is increasingly more acidic and a pH of 7.0 to 14 means the soil is increasingly more alkaline. Some plants thrive in either extreme, but for more general purposes, neutral pH is advisable. “Lawns require a pH of between 6.2-6.8 to perform to its best,” Adams says.
To correct low pH, add lime. For a high reading, add elemental sulfur or organic matter such as peat moss. It takes several months to a year for the change to become effective, so early planning and follow up is key. “With extremely low pH, it is not uncommon to correct the situation over a couple of seasons,” Adams says.
Excessive salinity is a common problem in sites near salt-treated roadways or in coastal regions. A white film or outline may be visible on a soil with excessive salt, or plants may exhibit signs of drought, despite receiving adequate fresh water.
A pH reading above 10 indicates the soil is too high in sodium, also called sodic soil. Such a soil will not properly absorb water. The addition of gypsum, sulfuric acid or a product containing calcium will help restore the imbalance. Another approach is to add organic materials to the soil to promote good drainage, enabling the salt to flush from the soil.
Compost, which is decomposed organic matter or manure, is a common soil additive that provides numerous benefits. It helps to feed the microbes in the soil, causing them to release valuable nutrients needed for plants and grass to flourish. Regular additions of compost will help to maintain soil quality and promote aeration.
Adding compost can also correct water issues. Soil that is too compact or high in clay will retain water, resulting in mildew and poor root development. Compost will help to aerate this type of soil and promote better drainage. Soil that is very sandy allows water to pass through it too quickly, preventing absorption. Adding compost to sandy soil will enhance its ability to hold water, improving retention.
“Soil is composed of many different living organisms that work to provide nutrients to the plants that it supports.” Jerry Schill, CEO, Schill Grounds Management
While many customers are happy to turn their lawn care and maintenance over to professionals, it’s a good idea to keep them in the loop when it comes to their soil requirements. Educating your customers deters problems and helps them to understand their landscape’s needs.
“We always tell our customers when we are going to do a pH test. When we get the results, we share those with our customers and discuss what changes or additions (if any) should be done,” Adams says.
Beneath every thriving plant or lawn is a carefully tended soil. Proper analysis and cultivation is the key to keeping each landscape healthy and pleasing to the eye.