Clay soil is very dense and can cause drainage problems for plants. It is common in many parts of the world and limits what can be grown. However, it can be corrected or altered to obtain a richer and more suitable soil for plants, flowers and vegetables.
Steps
Part 1 of 2: Part One: Prepare for Correction
Step 1. First of all decide if you want to give up growing plants that tolerate clay soil
It is probably the easiest option, and while you will be limited to certain plants and flowers, you can rest assured that they will have a very good chance of growth. There are few beautiful plants that tolerate clay well. On the other hand, many plants struggle to grow in this type of soil, despite the effectiveness of the correction. Choosing plants that like dry or particularly acidic soils can therefore be a losing battle from the start.
Step 2. Determine the pH of your soil
The first thing to do to correct it is to diagnose the pH of your soil. There are various types of tests, from DIY strips to professional kits. If you're a serious grower, go joint and get them one of their test kits.
- Get the professional kit. Instructions for use are included in the box. Send the results directly to the state lab. It may take a little longer than usual, especially in anticipation of spring, due to the many requests. You will receive a detailed analysis of the composition of the soil, the pH and the corrections to be made to make it optimal.
- The pH is a scale of acidity and alkalinity of the soil. It ranges from 0 to 14, with 0 implying maximum acidity, 7 a neutral soil and 14 a basic soil.
Step 3. Test the pH of the water
Correcting the soil to make it more acidic will not work if the water is alkaline and you intend to use it to water the plants. Don't get lazy, take a test on the water too. It is generally slightly alkaline, which may or may not be good depending on what you want to plant.
- If the water is basic, it will be "hard". Hard water is usually underground, which does not erode the pipes, taking residues with them. Acidic water is "light". It is obtained by removing calcium and magnesium.
- If you want to stay on the safe side, filter it out. Pure, filtered water is neutral. In this way, watering will not create problems with the pH of the soil, even if it can become expensive.
Step 4. Try a filter test
It will help you determine if the soil is draining enough. Dig a hole 60cm deep by 30cm wide. Fill it with water and wait for it to be completely absorbed. Now refill it taking into account how long it takes to drain the liquid:
- If it takes less than 12 hours you can safely plant anything that requires good drainage.
- If it takes 12 to 24 hours, you can plant plants that tolerate heavy or clayey soil.
- If it takes more than 24 hours for the hole to drain, you can only plant trees that can withstand the occasional flood such as balsam fir or red maple.
Step 5. Till the area
Spade deep for at least 15-20 cm. Add a few feet to the intended growing width. In this way the roots will be able to spread out if they need them.
If you don't have a subsoiler, you can use a pitchfork to aerate the soil. The advantage is that you will not disturb the essential structure of the soil, helping the microorganisms that live there. The disadvantage is that large clayey clods will remain
Part 2 of 2: Part Two: Correcting the Soil
Step 1. Do not work clay soil when it is wet
Wait for it to dry. Wet clay is less compact and therefore makes correction more difficult. You will need a lot of help to do this, so keep this tip in mind.
Step 2. Prepare to correct a larger section of land than you actually need
Measure the space you want to cover. Choose a large area. A small area can become a paradise for your plants, but as the roots begin to expand and encroach on the clay, they will fold in on themselves to return to where the soil is best. This will cause root bread problems.
Step 3. Correct the soil based on the test result
Most soils are alkaline, meaning you will need to lower the pH. There are many ways to do this. The most common substances to add are building sand, gypsum, manure, compost and other organic material.
- Building sand and gypsum allow for better drainage and increase air pockets which help break up clay particles.
- Organic compounds help plants by providing the necessary nutrients, and allow the growth of humus (not to be confused with "hummus") and microbes that build good soil. In addition, they help lower the pH by acidifying it.
- Try to mix the same amount of building sand and organic material. As you will distribute it over a very large area, think big: cubic meters instead of bags. Depending on the area you want to correct, many cubic meters of product may be required.
Step 4. For a 3x3 part area of 1, 3 cubic feet of organic material
It starts right from the staff. When it is integrated with the clayey soil, the material will begin to break down and become invisible. Don't worry, even if you don't see him he is doing his job.
Step 5. Then sprinkle one cubic meter of builder sand
Mix it thoroughly with the organic material and clay using a subsoiler. If you don't have one, you can rent it.
- If you can't find good quality sand, you can try green sand and chalk instead. They are more expensive but act in the same way to divide the clay particles, allowing a greater influx of water and air.
- Gypsum is particularly effective in areas where the soil has a high concentration of salt.
Step 6. Continue to monitor the soil pH frequently
Watch the changes. Most plants do not tolerate drastic changes in pH or soil, so you will need to be sure yours has reached its final point of balance before you start planting.
Step 7. Increase acidity if needed
Clay is usually quite alkaline. For this reason, you will find yourself having to vary the pH of the soil to make it more acidic. There are several ways to do this:
- Add an ammonia-based fertilizer.
- Add sulfur or iron sulfate.
- Add a compost of cottonseed and sphagnum or other types of compost.
Step 8. Avoid automatic irrigation systems
Since clay tends to retain moisture, automatic irrigation systems can flood the area and drown plants if you don't pay enough attention. Forget the sprinklers, save money and look at the plants to figure out how much water they need.
Advice
- Sometimes it is easier to choose plants that grow well in clay soils. The clay is so compact that it can be hard to dig to loosen and correct it.
- If there is no land office where you live, call greenhouses, gardening clubs, or go to plant stores to find the soil test. The university's agricultural faculty could also help you.
