One of the most important steps in setting up or maintaining a good garden happens before you plant a seed or seedling.  It is testing the soil where you plan to plant the garden. Depending on your soil’s natural fertility and the varieties that you choose to grow, the plants might perform for a while without requiring additional fertilizer. But sooner or later, the plants will show deficiencies by displaying stunted growth and, depending on the nutrients they lack, off-color leaves. A periodic soil test can inform you of nutrient deficiencies before they progress that far. In addition, a soil test can also provide information on soil acidity, the content of organic matter in your soil, and the soil texture.

Why do you need to a Soil Test?

Plants need nutrients to develop properly. While many of these nutrients come from fertilizer or compost that you add after planting, the roots absorb nutrients, as well as water and oxygen. Root absorption is the key to feeding and watering the garden. Soil conditions must be appropriate for a good root system to develop. A soil test lets you know which vitamins and nutrients are present in your existing soil. This includes major nutrients and micro-nutrients, all of which are important to the growth of your plants.

Nitrogen, phosphorus, and potassium are primary ingredients in fertilizer. Some of these will be at an appropriate level in your existing soil. Other minor nutrients contribute to growth as well. The test reports scientific levels of boron, calcium, copper, magnesium, zinc, and manganese found in your soil sample. If you regularly enrich your soil with an abundance of compost and other organic materials, micro-nutrient problems are unlikely.

Soil pH determines if your soil is acidic or alkaline. Most soils are in between, being in a neutral zone. The pH of the soil largely determines the vigor of your plants. Proper testing and results let you determine the type of fertilizer you should use in your garden. Aside from wasting money by using unneeded fertilizer, over fertilizing with the wrong nutrients can diminish plant health and make them susceptible to pests and disease.

Soil tests rarely determine nitrogen levels, a nutrient that is important for the plant. Nitrogen is readily lost from soil, escaping as a gas or percolating during rainfall beyond the roots. It is a difficult component to ascertain levels. Soil nitrogen is mainly locked up in organic matter, so verifying the quantity of organic matter in your soil offers an idea of the amount of nitrogen potentially available. If the soil contains about 4 percent organic matter, you probably have an acceptable level of nitrogen.

Soil tests do not tell you anything about soil drainage, insufficient sunlight, or insects and diseases. These threats to plants also can cause off-color leaves and stunted growth, so rule them out first before moving on to a soil test.

Sampling and results

Proper sampling technique is an important part of soil testing. To get a truly representative sample, dig in a few random spots around the test area and mix the soils together. Collect soil to a depth of 6 inches, which is approximately the depth of most plants’ roots. Remove any surface debris before digging for soil.

The sample soil can be taken to any soil testing lab or mailed to them. TNAU, Coimbatore has excellent soil testing facilities. Or you can purchase a soil testing kit. When you get the results of the soil test, begin the repair process as soon as possible, primarily by feeding the plants with the necessary supplements. Once you get the soil right, let the growing begin. With proper soil, that vision of a spectacular garden will become a reality.

The pH level greatly affects the fertility of soil and quality of plant growth. ? It measures the degree of acidity or alkalinity of your soil, both of which are vital to the health of your plants. Each influences the availability of essential nutrients in the soil. The pH scale has 14 units and is centered on 7, which is neutral. Levels below 7 are considered acidic and readings above 7 are alkaline. Soil nutrients are at their optimum availability in the range between 6 and 7. Most plants grow best in this range, although some type of plant growth can take place anywhere between 3.5 and 10. Fertilizer is of little use in acidic soils because it cannot be absorbed. It is important to test your soil because high pH levels can also indicate high levels of sodium in the soil that can also negatively affect plant growth.