Soil Testing

Reno County Horticulture
Soil Testing Information

The soil test is an excellent measure of soil fertility. It is a very inexpensive way of maintaining good plant health and maximum crop productivity.

Why Get a Soil Test?
Soil fertility fluctuates throughout the growing season each year. The quantity and availability of mineral nutrients are altered by the addition of fertilizers, manure, compost, mulch, and lime or sulfur, in addition to leaching. Furthermore, a large quantity of mineral nutrients are removed from soils as a result of plant growth and development, and the harvesting of crops. The soil test will determine the current fertility status. It also provides the necessary information needed to maintain the optimum fertility year after year.
Some plants grow well over a wide range of soil pH, while others grow best within a narrow range of pH. Most turfgrasses, flowers, ornamental shrubs, vegetables, and fruits grow best in slightly acid soils which represent a pH of 6.1 to 6.9. Plants such as rhododendron, azalea, pieris, mountain laurel, and blueberries require a more acidic soil to grow well. A soil test is the only precise way to determine whether the soil is acidic, neutral, or alkaline.

Most soil nutrients are readily available when soil pH is at 6.5. When pH rises above this value, nutrient elements such as phosphorus, iron, manganese, copper, and zinc will become less available. When soil pH drops below 6.5, manganese can reach a toxicity level for some sensitive plants.

The soil test takes the guesswork out of fertilization and is extremely cost effective. It not only eliminates the waste of money spent on unnecessary fertilizers, but also eliminates over-usage of fertilizers, hence helping to protect the environment.

When Should I Get My Soil Tested?
Soil samples can be taken in the spring or fall for established sites. For new sites, soil samples can be taken anytime when the soil is workable. Most people conduct their soil tests in the spring. However, fall is a preferred time to take soil tests if one wants to avoid the spring rush and suspects a soil pH problem. Fall soil testing will allow you ample time to apply lime to raise the soil pH. Sulfur should be applied in the spring if the soil pH needs to be lowered.

How Frequently Should I Get My Soil Tested?
A soil test every two to three years is usually adequate. Sample more frequently if you desire a closer monitoring of the fertility levels, or if you grow plants that are known to be heavy feeders.

Where Do I Take My Soil Sample?
You need to submit soil sample(s), completed sample submission form(s), and appropriate payment to the Reno County Extension Office. We will then send the sample(s) to the Kansas State University soil testing lab for analysis. The results will be returned to the Extension Office and the Horticulture Agent will make recommendations, which will then be mailed to you.

How Long Does It Take Until I Get the Results From My Soil Test?
Soil test results and fertilizer recommendations are usually mailed in two weeks, depending on the time of year and the number of samples the lab is needing to analyze. Make sure you fill out the form for the types of plants you grow or will be growing. Otherwise, no recommendations will be given. Indicate whether the crop is planted, or is to be planted. Incomplete forms may cause delays in receiving results and recommendations.

The information on this page comes from Ohio State University Extension Factsheet HYG-1132-99