Sunday, October 7, 2012

The importance of soil testing


Swift Horticultural Enterprises, LLC
Swift Horticultural Consulting

High Altitude Lavender
Curtis Swift, Ph.D.
450 Hill Avenue, Grand Junction, CO 81501


The importance of soil testing;

How to collect a sample, where to send it for analysis, and how to obtain a quality recommendation

Why is soil testing important?

·         To determine if the soil is appropriate for the trees, shrubs, flowers, herbs, lawn grasses, etc. you want to plant; not all soils can support healthy plant growth.
·         To learn what is needed to improve the health of those plants and reduce plant stress and reduce the potential for insect and disease problems.
·         To know what is needed to increase plant vigor, fruit, and flower production. 

A soil test provides the following:

·         What nutrients are deficient, the organic matter content, the pH and the soluble salt content.
·         What you need to add to the soil to correct deficiencies.

 You need the answers to the following items to realize the full potential of a soil test: 

·         Is this soil compatible with the plants you want to grow?
·         What nutrients are needed and when should they be applied and at what rate?
·         What nutrients should you avoid to prevent imbalances, excessive growth, root damage, etc.?
·         Are your plant problems the result of an improper fertilization program?
·         What nutrients are excessive and how can you avoid contributing to the problem?
·         Do you have a soluble salt problem and if so how can you correct it?
·         If the organic matter level of the soil is low how can you correct it without damaging established plants?  If this is a new planting what should you use and how much to improve the soil.
·         Is there a sodium problem and if so how do you correct it?
·         How can you enhance the growth and quality of the plants in this soil?


My job is to provide you the answers to the above questions.  My written recommendations will be specific to the plants you are growing or plan to grow in that soil. If you prefer the use of organic products in lieu of synthetic fertilizers I will provide you specifics on what products to use and how much of each is required for your plants and when they should be applied. 

Collecting a soil sample is simple. 

Shovel or trowel: Dig a hole in the area eight inches deep. Take a slice of soil off the side of the hole and throw it in a clean bucket, cardboard box, etc.  

Soil Auger or Probe: Twist/push the auger/probe into the soil to a depth of eight inches. Put the soil you collect in a clean pail, bag, or box.  

For more information on collecting a soil sample go to  Use clean tools to take samples.

 The soil testing laboratory needs about one pint of soil.  If the soil being tested is similar throughout the field or lawn take multiple samples from the area and mix them together for a composite sample.  If the soil appears or feels different in different parts of the field you should submit a separate sample for each soil type. If testing the soil around a tree, collect samples from the area half way between the trunk and the furthest reach of the branches and all the way around the circumference of the tree. 

 Air-dry the soil before sending it to the lab for analysis. Do NOT dry the sample on a newspaper or other surface where compounds can leach from the surface into the soil.  I use a plastic shoe box to dry the samples I mail to the lab. After the sample is dry, package it up in a plastic zip-lock bag. Keep the sample out of the sun after you have sealed the sample in the bag.

Where should you send your soil samples?

 I work with Ward Laboratories, Inc. in Kearney Nebraska (  Their analytical fees are reasonable and they are quick and accurate. Their S-4 Routine analysis provides the information I need to provide quality recommendations.   Use the sample submittal sheet at .  Make a note on the form to have them email the results to  Make sure your name, address, and email address is on the form. Please send me an email to let me know you have sent a sample to the lab so I will expect it.

 Mail the dried sample(s), sample sheet, and payment of $19.25 per sample to:

 Ward Laboratories, Inc.
4007 Cherry Ave., P.O. Box 788
Kearney, Nebraska 68848-0788 

When I receive the results from Ward Lab I will contact you to obtain further information to make my recommendations fit your situation correctly.  

 My Fee: 

My fee for providing recommendations and associated literature based on the soil test results is $30 per sample.  

If you live in the Grand Junction area and want me to pick up the sample(s) at your home or office, mail them to the lab, and provide you recommendations, my fee is $40 per sample.  Please contact me at 970.778.7866 if you prefer this option.