PH Of The Soil - Why Is It Important?

pH of The Soil – Why Is It Important

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If you want to have a healthy garden, soil is key. But not just any soil will do.

You need to consider various factors, one of the most important being the soil’s pH.

What does soil pH refer to? Soil pH is basically how acidic or alkaline the soil is. Too much of either is bad for soil. The ideal pH range for most plants is between 5.5 and 7.0. That said, many plants are able to withstand slightly different pH levels.

With that in mind, let’s take a look at soil pH and its importance.

It’s also important for you to know how to “fix” soil that has the incorrect pH level for your plants and grass to grow. In fact, this is one of the most essential things you should know how to do if you want a blossoming, thriving garden.

The Science Behind The pH Of Soil

ph of soil in the ground and elements

Ever wondered what pH stands for?

It means “potential for hydrogen” and it’s basically a measure of the relationship between hydrogen ions to hydroxyl ions, as Extension explains.

When we talk about soil pH, we’re basically measuring the hydrogen ions in the soil. How much there is in the soil determines how the ions are held to soil particles as well as organic matter, as the site goes on to explain.

The pH scale goes from 0 all the way up to 14. A pH of 7.0 means that the soil is neutral, or in scientific terms it means that the levels of hydrogen ions and hydroxyl ions are equal.

If a soil pH test comes out with anything lower than 7.0, then the soil is acidic. If it’s higher than 7.0, the soil is known as alkaline.

Why Soil pH Is So Important

Importance of Ph

Now that we’ve looked at what pH soil really is, it’s important that we consider why it’s such an important factor for any gardening enthusiast to know about.

If you don’t have the right pH in your soil for plants you want to grow, they will battle to grow and even die because they won’t have the nutrients they need to be healthy.

  • If there’s too much acid in the soil, some nutrients that the plants need won’t be available. These include phosphorus. In addition, other nutrients will actually become toxic instead of beneficial to plants, and an example is manganese. It’s clear that soil pH can be harmful to plants if it’s not correctly balanced.
  • On the other hand, if the soil is too alkaline, other essential nutrients will be unavailable for plants to use. These include iron, copper, zinc, phosphorus, and manganese. Iron is especially important because plants need high levels of this nutrient. Iron helps the plant to produce chlorophyll, and this is what gives a plant its beautiful green color as well as enough oxygen.

That said, it’s not just your plants that can benefit from having the correct soil pH.

It also has an effect on microorganisms that are in the soil and which can assist your plants to grow, as wikiHow reports. That’s why it’s so important to ensure that your soil has a healthy pH.

Can Acidic Or Alkaline Soil Benefit Some Plants?

Blueberries low pH soil

While most plants want a balanced soil pH that isn’t too acidic or alkaline, some plants actually want soil that’s a bit acidic.

For example, plants like blueberries, azaleas, and rhododendrons like soil that has a pH of between 4.5 to 5.5. If you’re battling with soil that’s a bit too acidic, then choosing plants that actually want this range of pH can help to make your job much easier and make your garden thrive more naturally. 

Similarly, there are some alkaline-loving plants that will grow if your soil is a bit on the alkaline side. These include lilac, juniper, butterfly bush, and forsythia.

What Affects Soil pH?

Soil PH affected by climate

There are many things that can affect the pH levels of your soil.

These include climate. Generally speaking, soils that are found in different climates will have different pH levels.

In dry climates, soil tends to be alkaline with high soil pH. On the other hand, humid climates produce acidic soil that has a lower pH, as reported by the Plos One journal.

Another thing that can influence soil pH by making it too acidic is nitrogen fertilizers that contain ammonium-N. When this substance gets transformed into nitrate by bacteria in the soil, it causes hydrogen to be released and that’s what makes the soil more acidic, as Brookside Laboratories explains.

How Can You Adjust Your Soil pH?

Imagine if you want to plant certain flowers or bushes but your soil just isn’t right for them.

Does that mean you’re limited to only having certain plants in your garden? No.

You’ll be glad to know that there are successful ways in which you can increase or decrease soil pH. A common way to increase the pH of your soil if it is too acidic is to use lime.

Quick word of warning before we continue: you should only make changes to your soil pH after you’ve tested the pH of your soil to make sure that it requires adjustments. You can purchase a soil-testing kit from your local nursery or hardware store.

If you’ve tested your soil and found that it’s high in acidity, some of the easiest ways to increase soil pH is to use powdered limestone or lime – it might be hydrated or come in pellets.

Pulverized lime is often a better choice because it is easily absorbed by soil and it’s more effective than pelletized lime. You should only use hydrated lime if you’re dealing with highly acidic soil because it works quickly to boost the soil’s pH, as wikiHow reports.

The best time to apply lime to your soil is approximately two months before you do your planting as this gives the pH a chance to change over time, so that’s something worth bearing in mind if you want to get started with your gardening tasks.

How To Decrease The Soil pH

aluminum sulfate for lowering soil pH

While lime is effective at increasing your soil’s pH, you can use organic materials to decrease pH, and this is an eco-friendly option that’s worth trying if you want to create an organic garden.

The use of materials such as compost can work well to decrease the soil’s pH but it takes a long time to work.

If you want something quicker, you’ll have to purchase aluminum sulfate from your local nursery. This is a compound that works faster to make the soil more acidic because it creates a chemical reaction that involves aluminum.

When applying it to the soil, make sure you till it into the soil. Afterwards, make sure you rinse your plants’ leaves as aluminum sulfate is quite harsh and can burn them.

Tip: If you’re making more adjustments to your soil pH in the future you must ensure that you don’t do so unless you’ve tested the soil again otherwise this could throw its pH out of whack and give you more problems than what you started with!

Related Questions

What does tilling the soil mean?

While it might sound complicated, tilling the soil basically means turning over and breaking up the soil, as SF Gate reports.
You don’t need fancy equipment to till your soil – simply use a shovel, preferably with a long handle.

Does water affect the acidity of soil?

Groundwater tends to be more alkaline, but rainwater is more acidic. So, if the plants you’re growing get a lot of rainwater, then the soil that’s nourishing them might be acidic, as wikiHow reports.

Groundwater well

Can mowing your lawn too much affect soil pH?

Although mowing does increase the amount of moisture in the soil because debris that’s caused by it can limit how much sun can get to the soil, you’ll be pleased to know that mowing in itself doesn’t affect the soil pH, as Grinnell College reports.


It’s clear that the pH of your soil is very important if you want your garden to thrive.

In this article, we’ve looked at what soil pH is and how it affects your plants, as well as how you can test and adjust the pH of soil.

Your garden thrives by being delicately balanced and the pH of your soil forms a big part of that balance you need to strike so that your plants and grass can survive.

After following the advice featured in this article, you’ll be well on your way to having the garden of your dreams.

Last Updated on August 20, 2022 by Gustaf Johansson

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