A 5-Step Guide To Effective Soil Evaluation

Soil evaluation is an incremental part of building your dream lawn. Basically, it is all about soil texture – which is the relative proportion of sand, silt and clay particles – as a factor that must provide a healthy environment for your roots. If your soil is not prepared well, your home lawn would never exceed your expectations.

Generally speaking, soils that contain more than 40 percent of clay (as the smallest mineral particles) are easily compacted and often lack spore spaces. 

So, how do you evaluate the texture of your garden soil?

Step 1: Collect Soil Samples

The first step is to collect soil samples and send them to a laboratory or do the test yourself. Lab tests from state universities nowadays cost around $20 including the return postage, which makes them a real bang for the buck.

However, in order to collect soil you must know how to properly do it:

  1. Use a clean and rust-free trowel with which you can take samples from up to 10 areas of your lawn
  2. Dig several holes into your lawn that go from 6 to 8 inches in depth
  3. Take the slice of soil from one side of each hole and save 1 to 2 inches from the middle of the slice and later discard the top and bottom
  4. Mix the samples in a clean container and allow them to dry at room temperature before you send them to the lab

If you want to try a soil test by yourself, the best way to test your own soil is to get a professional kit that determines the pH or nutrient levels. This will give you a general idea of your soil’s deficiencies and allow you to monitor the progress of the soil improvements that you will make.

The pH rating means how much acid or alkaline is present in your soil. The pH range that is recommended is 0-14 with 7.0 as the mid-point which means 1/2 acidity and 1/2 alkalinity. So, the basic pH test can give you a rough idea on the acidity and alkalinity levels of your soil and is one of the easiest ways to figure out if your soil needs improvement.

Step 2: Eliminate Weed Problems

Therefore, eliminating the weed problems existing on the site is the first step you need to do. You must control the perennial weeds such as quack grass or tall fescue prior to lawn seeding or sodding. Now, the best way to control these weeds include digging by hand, repeated soil tillage or using a herbicide that is systemic (moving with the plant). There are also many organic products that are becoming more and more popular. It is up to you to read their instructions, understand and follow all the label directions when using each or any of them.

Step 3: Add Organic Matter Where Needed

It is always important to thoroughly work the soil. If your soil is poor (heavy clay), the best way to amend it is by adding organic matter. You can get compost, rotted manure, peat moss and quality topsoil to do this. However, make sure to never choose sand as an option – as it is not recommended for home lawns.

Using organic matter can also benefit the microorganisms that work together with the roots of the plants and prevent any harm to your soil. There are numerous benefits of using organic materials into your existing soil. If you are doubting how to use them, it is best to incorporate these materials into the existing soil rather than layering them on the surface. The end result should be a well prepared soil of six inches (or more if there are big trees surrounding it).

Step 4: Use Starter Fertilizers Into The Soil Surface Prior To Lawn Establishment

Another important factor of soil evaluation are starter fertilizers – which are essentially products that should be mixed into the soil surface before establishing the lawn. These should be high in phosphorus. Typically, the balanced fertilizers have balanced ratios of nitrogen, phosphorus and potassium (ex. 10-10-10 or 12-12-12) and are therefore a great alternative if starter fertilizers are not available.

Step 5: Establish A Favorable Final Grade

Establishing a favorable final grade is important when preparing the soil. This should include covering any rock or other debris as it may cause problems for the grass later. By eliminating these depressions or raised areas, you will ensure proper conditions for your soil.

Also, soil preparation should be done when the soil is not too dry or not too wet – mainly because of the tillage that can destroy the soil structure and create problems with the air and water holding capacity and drainage after rain.

A Final Word For The Wise

The best way to improve your soil is to first understand what you have in order to apply the right amendments. The best time to test your soil, on the other hand, is spring – right before you add any compost or other amendments. However, your soil can be tested at any time.

Instead of taking shortcuts in soil and site preparation, you can prevent a lot of lawn problems by properly evaluating the soil and taking the time and effort to do a thorough job before seeding or sodding.

In the end, effective soil evaluation is a process that includes soil testing, nutrient and soil amendments as well as creating certain uniformity of the subsoil and final grading.