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Every plant has a preferred range of soil acidity or alkalinity. When that range is not met, a host of ills may follow. If you are trying to reduce the pH of your garden, you are probably trying to raise blueberries, blue hydrangea, silver maple, or azaleas.
To help them grow, you need to make the soil acidic, which involves lowering the soil pH. There are quite a few natural ways to reduce the pH of garden soil over time.
Using organic materials like well-decomposed compost, compost tea, elemental garden sulfur, mulch, coffee grounds, and sphagnum peat moss in your garden can help lower the pH of the soil naturally.
As a gardener, one must understand the perennial relationship between a plant and the soil. A wide range of soils consists of varying amounts of minerals, air, water, dead organic matter, and living organisms.
Understanding soil and its components can help plants thrive. Let us answer some of your questions specific to soil pH and talk about ways to increase the acidity of your garden naturally.
What is pH?
The acidity or alkalinity of a substance is measured in pH units and measured on a scale from 0 (extremely acidic) to 14 (extremely alkaline), while seven were neutral.
Soils usually range from a pH level of 3 to 10, depending on the soil’s parent material and the annual rainfall the area receives. While some plants enjoy slightly acidic conditions, some thrive in neutral conditions, and some in alkaline conditions.
What does Soil pH do?
Soil pH has indirect effects on plants which can still be wide-ranging. It can affect plant nutrient availability, crop yields, suitability, and soil micro-organism activity.
For instance, insufficient soil acidity can result in young leaves’ yellowing, indicating iron deficiency. Besides, pH can influence soil-dwelling organisms like earthworms, nematodes, protozoa, fungi, and bacteria.
Their well-being can also have an impact on soil condition and hence the health of the plant.
What Are the Factors That Affect Soil pH?
The intrinsic factors influencing the soil’s pH level include climate, soil texture, and mineral content. The natural soil pH also shows the impact of the soil-forming factors such as parent material, topography, time, climate, and organisms. Let us understand this better:
Temperature and Rainfall
Temperature and rainfall can impact the intensity of leaching and weathering of soil minerals. Thus, soil pH decreases over time in warm and humid areas. However, in dry environments where leaching and weathering are less intense, the soil’s pH level is more likely to be neutral or alkaline.
Soil Texture and Organic Matter
Soils that hold a high percentage of clay and organic matter are more resilient to changes in pH. This means that they have a higher buffering capacity than sandy soils.
Though you cannot change the clay content in the soil, you can easily alter organic matter content. On the other hand, sandy soils usually have a low organic matter content, resulting in a lower buffering capacity.
Thus, they have a higher water percolation rate and infiltration, making them susceptible to acidification.
How to Test My Soil?
You should conduct a soil test before increasing or decreasing your soil’s pH. This will help in the determination of the current pH of the soil. Follow these steps to analyze the pH level of your soil:
- Dig around 4 to 6 inches on the surface of your garden to get a sample
- Make sure there are no stones, large clumps, or other debris in the soil
- Add distilled water into the soil to create a muddy mixture
- Pour the sample through a coffee filter into a clean glass (obtaining only the solids and allowing the liquid to pass through)
- Dip the pH test strip into the liquid
- Repeat this process several times with different samples from your garden to get an average pH level.
- What if My Garden is Too Alkaline?
Soils with a pH level of more than seven are considered alkaline. And if your garden soil is too alkaline, you should try spending your time, effort, and money on something that could fetch you healthy and happy plants. Acidifying or even neutralizing your garden soil may take a lot of time.
Thus, working with local nurseries or personnel in horticulture and agriculture is better. This can help you know which plants are better equipped for alkaline and calcite-rich conditions. Lavender, yarrow, kiwi, and calendula are some options you can consider, as they do not mind alkalinity.
How to Naturally Reduce Soil pH?
Once you have got the results, and the acidity of your soil is lesser than the recommended acidity for the plants you are planning to raise, you can go ahead with the following ways to get a lower pH level and increased soil acidity:
You should add plenty of well-decomposed compost the next time you plant. It will help lower the pH of your soil over time. Moreover, it will offer a wide range of benefits for plant growth, improve the soil structure, and add micro-organisms into the soil that can prove extremely beneficial.
You can water your plant with compost tea, an organic way to lower the soil’s pH level. Also, it is a nice way to feed your plants as it offers fast-absorbing nutrients. It may even help protect the plants against some diseases and pest issues.
Elemental Garden Sulphur
One can also apply organic elemental garden sulfur. Soil bacteria change sulfur to sulfuric acid, which, in turn, lowers the soil pH. Since sulfur is an essential nutrient, it can bolster plant disease resistance. However, it can reduce your soil’s pH significantly, making it important that it is used in moderation.
Organic mulch in your garden beds is another great way to make the soil more acidic. This breaks down gradually and can give your garden an acidic boost. You can use pine needles or oak leaves since organic mulches have several benefits.
It can help decrease soil erosion, retain moisture, regulate temperature, and release useful nutrients into the soil.
Do not toss away the remaining grounds the next time you brew a cup of coffee. They can do wonders for your garden. Just sprinkle them around your garden or add them to the compost pile.
The coffee grounds will break down, making your soil more acidic. Moreover, your soil will get the right ingredients and benefit from better water retention, drainage, and aeration.
Sphagnum Peat Moss
Sphagnum peat moss is sphagnum moss’s dead, decayed, and fibrous plant matter. It is a great soil amendment for acid-loving plants and can help retain moisture in the soil.
However, it takes several millennia to form, so it is not considered a renewable resource. Due to environmental concerns, people feel a twinge of guilt in using peat moss for gardening or other uses.
What Should I Do After Amending the Soil?
You should retest the soil every few months and constantly check the soil’s acidity. This will help you know whether you used the correct method, the right quantities and whether it is still working. This is important since different amendments can last different periods.
How to Maintain The pH Level of My Garden?
You cannot put it out of your mind when you have attained the required pH level for your garden. You must test the soil periodically to know its pH level and amend it accordingly. Naturally, alkaline soils will shift the pH scale due to the rock minerals in their formation.
Thus, practices like collecting natural rainwater and watering them to imitate nature can be useful in maintaining the soil pH. This is because normal tap water can be tough and have a high pH.
So, it is important to remember that altering soil pH is a slow process and might require repeated or even a combination of treatments.
Altering the pH level of your soil and making it more acidic can be quite challenging for some gardeners. This is for several reasons. For starters, water is often alkaline. Also, limestone within the soil is constantly breaking down, making it alkaline.
This can make it a constant struggle for gardeners to correct the pH level of their garden soil. However, with these organic methods, you can lower the pH level of your soil organically. We hope that you can raise various acid-loving in your garden.
Conclusion to Natural Ways Can I Reduce the pH of My Garden
There are plenty of natural ways to reduce the pH of your garden soil. It is important to note that you do not have to do the entire garden. A raised or even separate bed can be altered individually, creating micro conditions for each plant type in your garden.