Testing soil can be time consuming and expensive! Often times as gardeners we send in a soil sample to try and find out the quality of the soil, what the pH is, and what nutrients can be found. For a beginning gardener, this information is extremely valuable to know, and can truly mean the difference between a great garden, and a complete failure of a garden. In this tutorial we will look at how to find the 3 major concerns of soil; Composition (texture), pH, and Macronutrient (N-P-K) makeup.
How to test the texture:
1. Take soil from a depth of 3-4 inches below the soil.
2. Mix enough water to become thick and tacky
3. Take the soil clump (about a tablespoon worth) and roll it back and forth between your hands.
4. Measure the ribbon:
– If the ribbon is longer than 2 inches in length you have CLAY
– If the ribbon is an inch you have LOAM
– If the ribbon is less than an inch, or breaks before forming a ribbon, your soil is SANDY
Pros: Good nutrients, good mineralization, dries out less frequently
Cons: Dries hard, poor root penetration, poor drainage, poor root aeration.
Pros: Good drainage, good root aeration, good root penetration
Cons: Poor nutrient levels, dries out quickly, poor nutrient holding capabilities
Pros: Good drainage, good nutrient holding capabilities, good root aeration, good moisture holding capabilities
Cons: light weight soil can be blown away by hard winds, and carried away by heavy rains
How to test soil pH based on texture:
1. Based on the test above:
Sand = Acidic (5.5 – 6.9)
Clay = Alkaline (7.1 – 8.0)
Loam = Neutral (7.0)
**These are general pH ranges based on texture. For a more accurate gage, a pH tester can be bought for less than $15
How to test soil nutrient levels based on texture:
1. Based on the first test:
Sand = Low nutrients (Nutrients will leave sandy soil whenever it rains)
Clay = High mineralization and Nutrients (Clay binds nutrients and minerals and nutrients do not leave quickly)
Loam = Fertile with sufficient nutrients (A perfect combination of drainage, nutrients, and aeration)
**These are general assumptions of soil based on it's texture. It is highly accurate for a rough estimate of soil fertility, but will not be 100% accurate.