Self-sufficiency is becoming increasingly popular. But at the same time, questions arise about he althy plant growth. To achieve high yields, you should examine your garden soil a little more closely. Soil analyzes provide valuable information about the properties of the soil.
Why is a soil analysis important in the garden?
A soil analysis provides information about the nutrient content, pH value and soil type of the garden soil. For hobby gardeners there are analysis packages starting at 20 euros. Samples should be taken from different depths (15-90cm) depending on the usable area in order to obtain meaningful results.
Why soil analysis is important
In agriculture and arable farming, detailed examinations are important for optimal yields. A soil analysis provides information about the nutrient concentration in the soil. Nutrients are essential for he althy growth. However, the availability of nutrients is influenced by several factors. To get reliable results, you should send a soil sample to a laboratory.
Soil analyzes provide information on:
- Nutrient content
- pH value
- Soil type
Soil is a sensitive structure whose properties influence plant growth.
What is examined in a soil analysis
During a soil analysis, various aspects can be examined
There are various soil analysis packages for hobby gardeners that are aimed at specific parameters. The standard test examines the soil for the concentration of nutrients and trace elements that are important for plant growth.
If you would like to find out about the nitrogen content in the soil, you must book special analysis packages. This investigation involves increased effort because nitrogen is usually present as nitrate and is mobile. The concentration fluctuates greatly over the course of the year because nitrate is washed out by heavy rain.
You can also have the substrate from your garden checked for harmful substances. Heavy metals are a natural component in the soil and dissolve through weathering. The toxic substances can also accumulate in the garden soil through exhaust gases, contaminated sites or topsoil from unknown sources.
| Investigation | Result | |
|---|---|---|
| Soil nutrient analysis | Soil quality | Fertilizer recommendation |
| Soil test for pollutants | Heavy metal pollution | understandable analysis report |
| Yield soil analysis | available mineralized nitrogen | Fertilizer indication |
| Soil analysis nutrient by culture | Nutrient analysis with focus on cultivated plant | Fertilizing tips |
Costs of a soil analysis
Hobby gardeners can also take advantage of soil analysis. Prices vary depending on the test chosen. A simple soil analysis costs around 20 euros. Included are analyzes of soil type, pH value, humus content and concentration of important nutrients and trace elements. More complex analyzes that check the concentration of nitrogen, other trace elements or heavy metals cost between 50 and 90 euros.
Soil analyzes are offered here:
- Raiffeisen laboratory service
- Agricultural investigation and research institutes (LUFA for short)
- Pharmacy Laboratory
- Soil Analysis Center Reblu GmbH
Buy sets
Dehner offers a soil analysis set for around 20 euros, which includes a shipping bag and instructions for taking soil samples. The sample is then sent to a laboratory for analysis. To see the results, you need to download a special program. In addition to the analysis results, you will also find fertilizer recommendations here. Sets with a broader analysis spectrum are also available from the soil analysis center or pharmacy laboratory.
Do your own soil analysis
Depending on the type of soil analysis, you can also do it yourself
The possibilities for independent soil analysis are limited because the majority of all parameters cannot be researched without special means and equipment. The costs for such equipment are in the range of several hundred euros and are therefore not worthwhile for private use. However, you can determine the soil composition and pH value yourself.
Tip
In spring, many garden centers offer free soil analyzes.
Take soil sample
The type of use is important because this determines the depth at which you should take the soil sample. To ensure that the soil provides the most meaningful results possible, you should take around ten samples from different places in each usable area. To do this, use a dandelion cutter that is stuck vertically into the ground and slowly pulled out.
How deep you should pierce:
- Lawn: ten to 15 centimeters deep
- Vegetable garden: 20 to 25 centimeters depth
- Perennials: 20 to 25 centimeters depth
- Permanent crops: 90 centimeters depth
- Woods: 90 centimeters depth
You get a cross section through different layers of the earth. The samples from a usable area can then be mixed or analyzed individually. To reach greater depths, you should get a drill stick. This can be purchased or rented from garden centers.
Check soil composition
Basically, the soil types clay, silt and sand differ depending on the grain size proportions. Clay contains all three grain fractions, which can be present in different proportions. The soil properties depend on the dominant grain fraction.
| Moldability | Consistency | Texture | |
|---|---|---|---|
| clay | variable | variable | variable |
| Sound | easy to shape | sticky | leaves dirty marks, shines |
| Silt | moderately malleable | little sticky | velvety-floury to rough |
| Sand | not malleable | grainy | crumbled, crumbly |
finger test
You can test the rough soil composition yourself with a simple finger test. Lightly moisten the soil from the sample and take a tablespoon of the substrate in your hand. Next, try forming the substrate into a pencil-thick roll. This works differently depending on the nature of the soil.
Either the substrate crumbles or it can be shaped. In this case, you can continue kneading and shaping the sausage. Pay attention to whether the substrate becomes cracked or tightened. Crackling noises indicate a sand content.
How to test soil composition:
- Substrate not malleable, does not adhere to the hand lines: sand
- Substrate not malleable, not cohesive, floury: silt
- Substrate not malleable, gray-black color, with organic residues: humus
- Substrate malleable, matt surface: clay
- Substrate very easy to shape, does not crack when rolled out, shiny: clay
Einfache Bodenanalyse - Der Grüne Tipp
Determine pH value
The pH soil test (€4.00 on Amazon) from Neudorff, which you can buy from Obi, for example, provides information about the pH value using color reactions. To do this, add some soil to the test bottle included and fill it up with distilled water. After a test tablet has been added, close the container with a cork and shake it vigorously until the tablet is completely dissolved.
The sample is left standing for about half an hour so that the soil can settle. You can then compare the color of the water with the enclosed color palette and read the pH value.
Soil testers hardly provide usable results
If you want to test the pH value and other things in your soil, you should invest a little more money
There are devices for independently checking pH value, light incidence and humidity. The market offers inexpensive models that cost between five and 20 euros and work with or without a battery. Such devices are usually unusable because they only provide rough guideline values or cannot correctly determine the pH value.
Tip
If you are interested in a soil tester, you should not go for the cheapest models.
Soil analysis with a Fertometer
Such devices are equipped with a brass probe that measures the conductivity of the soil and thus the amount of ions in the substrate. When nutrient s alts dissolve in moist soil, they are available to plants. These so-called EC measuring devices (English: electrical conductivity) measure the concentration of soluble s alts and show whether the nutrient supply is OK or the substrate should be fertilized. The probe is inserted into the substrate. A button is pressed to begin the measurement. The device then gives fertilizer recommendations using three LEDs.
Disadvantages:
- no detailed information about nutrient composition
- no statement about nutrient replenishment through the breakdown of organic substances
- no information about the ratio of the nutrient s alts to one another
Excursus
Electrical conductivity
For a substance to be conductive, it must have many freely moving charge carriers. Metals have charge carriers in the form of loosely bound electrons, but ions also serve as conductive molecules. Ultrapure water has a certain conductivity, which is increased by the addition of s alts. These release ions in aqueous solutions.
The electrical conductivity is given in Siemens per meter. During the growth period of a plant, an electrical conductivity below 0.35 mS/cm is too low. The fertometer lights up yellow and indicates that more fertilizer should be used. A value of more than 1.0 mS/cm is harmful to the plant in the long term because too many s alts are dissolved and therefore available to the plant. The device lights up red.
Frequently asked questions
Who needs to carry out a soil analysis?
There is a fertilizer regulation that is required for agricultural operations. Accordingly, farmers must have soil nitrogen determined through a laboratory analysis once a year. You can also use results from comparable areas and determine the fertilizer requirement accordingly. The values are published in agricultural weekly newspapers. It is mandatory to carry out an analysis of phosphate on areas larger than one hectare, which is carried out at least every six years.
Why is phosphate determination so important?
Phosphorus is a vital substance for plants that is present in the soil in the form of various phosphates such as potassium, calcium or magnesium phosphate. The availability of phosphorus is highest at a pH between 6.0 and 7.0. However, excess phosphates can be washed out, causing them to enter groundwater, surface water and other ecosystems. With the help of a phosphate determination, appropriate fertilization can be determined.
What are DWD soil analyzes?
The German Weather Service (DWD for short) carries out soil analyzes to create soil weather maps. These provide information on numerous meteorological factors such as visibility, wind, clouds, air pressure and air temperature. This soil analysis therefore has nothing to do with the analysis of the substrate in your own garden.
What is soil analysis according to LAGA?
The State Working Group on Waste (LAGA for short) is concerned with the enforcement of waste law in Germany. The LAGA is mainly important for construction and renovation measures. This results in excavated material that must be thoroughly examined through soil analysis. This is checked for various hydrocarbons, pH value and heavy metals, among other things. Although such analyzes are not necessary for private house construction, they can also be used by private individuals. The examination of a soil sample costs 600 euros.
