Dozens of factors influence plant development. It is not enough just to achieve high fertility, a good supply of humus and nutrients, and ensure a stable supply of moisture and favorable temperature conditions. A special place among the influencing factors is given to the acidity of the soil intended for cultivating plants. Moreover, we are talking about both indoor and agricultural plantings.
What does soil acidity affect for plants?
The ability of plants to absorb nutrients and macro- and microelements dissolved in water depends on the level of acidity.
This also affects other indicators:
- Physical properties of soil. If the acidity is too high, it becomes acidic, which makes it difficult to absorb some nutrients. On alkaline soils, iron absorption decreases, leading to plant diseases, for example, chlorosis, accompanied by yellowing of leaves.
- Inhibition of the activity of a number of soil microorganisms.
- The level of compounds dissolved in water that are toxic to vegetation (manganese, boron, iron, aluminum, etc.) increases.
For fertility, the optimal soil pH level is of great importance, which is within the range of 5.5 in the upper layers and 4.8 in depth. This suits most plants, allowing them to fully absorb the necessary elements and successfully assimilate them.
What does it depend on
Soil acidity is associated with its ability to exhibit properties characteristic of acids. The soil solution contains hydrogen ions, as well as exchangeable aluminum and hydrogen ions in the absorbing complex with incomplete neutralization, which gives the soil an acidic reaction. The more there are, the higher the acidity level; the less, the lower it is.
Acidity is not a stable indicator.It may change depending on fluctuations in external conditions, for example, with significant precipitation, the introduction of certain substances and fertilizers, the activity of soil microorganisms, and so on.
It is important to control it, especially if plants with certain requirements for the acid-base balance are planted in the soil mixture. For example, if the acidity level changes for plants that require acidic soils, their leaves will signal this by first yellowing and then wilting. This is a clear indicator that due to a change in the acidic reaction to the alkaline one, the roots stopped absorbing the necessary micro- and macroelements, which led first to disease and then to the death of the flower.
How to determine it
In order for plants to grow successfully, be strong and healthy, you need to monitor the acidity of the soil. This is especially important when growing indoor plants that cannot adapt to the soil composition due to the limited volume of soil in the pot, as well as due to their acidity requirements. However, this does not mean that ornamental and agricultural plants in open ground are less in need of acidity testing. They are also demanding of its level.
A variety of methods and tools are used to measure pH levels.
Litmus test
This is the easiest and most affordable way to test soil acidity. It will require inexpensive litmus paper, which can be purchased at your nearest pharmacy.
To measure acidity, you need to take several soil samples from different areas. They are wrapped in a clean rag, placed in a washed glass container, and filled with distilled water. You should not take water from the tap, as it may affect the measurement result.
After a five-minute interval, you need to quickly dip the litmus paper into the water. Its reaction will show the pH level: in acidic soils it will turn red and orange, neutral soils will give all shades of yellow and green, and alkaline soils will be blue and purple. The more saturated the color, the higher the level.
pH meter
This is a device for determining the pH value. It is used not only in agronomy, but also in many other industries where environmental control is important. This device is available in dozens of versions, including for use in indoor floriculture and in the garden.
Since a neutral level is preferable for most cultivated crops, regular pH measurements make it possible to detect changes in the direction of acidity or alkalinity and take appropriate measures in time.
Traditional methods
In addition to expensive methods and devices, the condition of the soil can be determined using fairly simple methods.
Indicator plants
They will not give accurate readings, but they can easily divide soils into alkaline, neutral or acidic. To do this, you need to find out what plants grow on the site:
- If it is dominated by mosses, as well as buttercups, meadow grass or field pike, white grass, the soil is acidic.
- Wheat grows and overwinters well on neutral soils, and alfalfa and clover thrive.
- Alkaline soils are loved by cloves, asparagus, leeks, and currants (red and white).
Most plants prefer neutral soils or medium pH levels towards acidity or alkalinity.
Vinegar
You can test the soil at home with ordinary vinegar. By dropping it on the ground, you can get the following results:
- Alkaline earth will react violently with foam.
- Neutral - a little foam.
- Sour – no manifestations.
It must be taken into account that the soils in one area may vary, especially with strong changes in relief.
Chalk
This method is the opposite of the vinegar test. It can be carried out at home or in the country. Chalk will foam when reacting with acidic soil, will show no effect on alkaline soil, and will show minimal effects when in contact with neutral soil.
Grape juice
This method will help determine the acidity in the area if you don’t have vinegar or chalk on hand.
Visually
When examining the site, you can notice a whitish tint, characteristic of acidic podzolic soils. You can also pay attention to the color of the beet tops. On neutral and slightly alkaline soil it is green with burgundy lines. The higher the acidity, the brighter the red color the tops acquire.
Types of acidity
There are the following types of acidity:
- Current. It represents the pH level of the soil solution. pH is a sign. This is a neutral level, below it the reaction is acidic, above it is alkaline.
- Potential. This is the acidity of the solid part of the soil.
- Exchange. It is caused by exchangeable aluminum and hydrogen cations passing into solution from the soil absorption complex upon interaction with neutral reaction salts.
- Hydrolytic. This is the pH of the extract with a solution of hydrolytically alkaline sodium acetate.
Too high and low acidity levels are toxic to the root system of plants, so monitoring the pH level is an important way to maintain the fertility and health of plantings and obtain a large harvest.
