Soil problems are easily fixed

Soil problems were once thought to be largely fixed characters that you could do little about. Now we know better. The answer to most soil problems lies in soil balance and the Mikhail System.

So exactly what sort of problems are we talking about? In fact, its probably easier to ask what problems we are not going to talk about. Essentially, if you want to know about nutrient deficiencies and fertilizer problems, you can find that on another page.

If your soil is hard, acid, compacted, poorly drained, then read on - this is the page for you. The soil conditions dealt with here will need Lime, Dolomite and Gypsum rather than fertilizer. If you are wondering what these materials do, we have a separate page on that topic.

Problems with Wet Soil

A common problem is seen when the soil wets easily, but then becomes sloppy and forms a crust when it dries out again. This type of soil is called "Sodic", but in fact there are a number of conditions that get lumped under this term. Essentially, these problems are caused by high levels of Sodium and/or Magnesium in the soil. These soils may also be saline (salty), but the condition is seen in non-saline soils as well.

The treatment for these soils is to apply Gypsum (in the right amounts), however, soils that are both sodic and saline will need specialist advice for proper treatment. One cruel twist, however, is that in very saline soils, this condition may not appear until after the salt has been leached away. For this reason, an accurate soil test and proper advice is essential in getting a good result.

A common problem in treating these soils relates to poor sub-surface drainage . Often there may be a restrictive or impermeable layer not far below the surface. Water will 'perch' on this layer and be drawn back to the surface by a process called "capillary action" - concentrating salts in the root zone and continually making things worse.

In such cases the use of gypsum should be avoided - until such time as adequate sub-surface drains can be installed.

My Soil Sets Hard when Dry

This is quite a common problem and is caused by a low Calcium-Magnesium ratio (ie. Ca:Mg < 2.0) in soils with an acid pH. In other words, the Calcium level (as a percentage of the CEC) is low and this reduces the Ca:Mg ratio, sometimes even when the Magnesium level is itself not especially high. So, when you look at the Calcium and Magnesium levels as percentages of the Cation Exchange Capacity (CEC), then you will usually find Calcium is less than 40% and Magnesium is 20% or more.

This topic can get a bit complicated, so we have a separate page with all the details.

Treatment of these soils requires application of Lime, but sometimes a combination of Lime and Gypsum is needed.

My Soil has an acid pH

Outwardly, there may be no visible symptoms (in fact pH is itself a symptom, not the cause of soil problems), but these soils often have poor structure and may or may not be hard-setting.

Some soils are naturally acidic, while others are at risk of becoming acid, but both these soil problems are treated the same way - by applying Lime. Of course, if the soil is also low in exchangeable Magnesium, then Dolomite or some combination of lime and Dolomite will be needed.

Water logging and compaction

These soil problems can occur with virtually all the previous ones and so it is important to base soil improvement treatments on the results of reliable soil tests, rather than rules-of-thumb that relate only to the symptoms of a problem.

Soil structure decline

This is estimated to be the most widespread and yet least recognized of the soil problems. It is caused by excessive or inappropriate cultivation and is most common in areas where people try to overcome other soil problems with nothing more than brute force.

Again, the key is to base decisions on a reliable soil test. You should also avoid cultivation when the soil is damp, since this is when the most damage is done. Lastly, plan your gardening activities so you cultivate as little as possible.

Further Reading

Using the Mikhail System to improve soil
Developed from scientific research conducted over the last 45 years, The Mikhail System provides a reliable process for improving any soil.

Calcium-Magnesium ratio
This is an important and largely mis-understood measure in soils.

What is Cation Exchange Capacity (CEC)?
This is an important characteristic of any soil, but one that many people have trouble with - largely due to the technical jargon involved.

The latest research on Soil Biology
New research is leading to a better understanding of the importance of soil biology and its real place in the functioning and productivity of soils.

Reading soil test reports
The only way to reliably improve soil is by using a detailed soil test, but understanding what all the results mean can be tricky.