Adjusting the pH levels of your soil is one way to improve your plant’s health and nutrition. Even a shift of a tenth of a level can make the difference between a healthy plant and a very healthy plant. The good news is changing the pH levels of your soil is fairly simple.
Before reading ahead, a couple things:
First, only adjust the pH level of your soil if necessary. For a vast majority of plants, you want to have a neutral level for your soil, a pH level of 7. Unsure how to test your soil? You can easily test your soil using vinegar and baking soda.
Lastly, while these methods of are quick and easy to do, it will take a few months for your soil to shift its pH levels. As a result, the improvement to your plant and garden’s health will take time; just know that these simple steps will add nutrition to your soil.
With that in mind here are some simple ways to either increase or decrease the pH levels of your soil.
How to increase the soil’s pH level (more alkaline)
When your soil’s pH level is under seven, the soil may be too acidic. You may need to increase its pH level and make it more alkaline. There are two simple ways to increase your soil’s pH level: adding powdered limestone or adding wood ash.
Adding Powdered Limestone
You can find powdered limestone or lime in almost any garden store, which makes it highly accessible. Aside from increasing the soil’s pH level, powdered limestone also supplies nutrients, calcium, to you soil. Tomatoes and peppers are some plants that benefit from calcium
White in color you can apply limestone just like that, image from RHS
Application: To apply the powdered limestone to your garden, simply grab the power by the handful and sprinkle it over the soil. Less is more here as you only want to lightly dust the soil. Then you can use your hands or a fork to gently mix the limestone with the soil. Water the soil afterwards.
If you already have plants in the soil take caution when sprinkling the powdered limestone. Avoid covering the plant’s leaves with limestone.
Note: Dolomite is a similar substitute to limestone, but not the same. We recommend sticking to limestone whenever it is available.
Adding Wood Ash
The remnants of your bonfires or fireplaces in another good source for increasing your soil’s pH level. While wood ash is not a common find in garden stores, we added this as an option for anyone who may have this available. Wood ash also provides soil with nutrition, potassium, and can also keep your garden safe from certain pests and diseases.
Sprinkle the wood ash close to your plants, image from Orange Post
Application: Applying wood ash is similar to applying powdered limestone. Lightly sprinkle the ash on the soil, avoiding any plant leafs. Less is more here too; a thin layer on the soil should do. Water the soil afterwards.
These are a couple simple ways you can increase your soil’s pH level. After applying either of these techniques, remember to test your soil again after three to six months.
How to decrease the soil’s pH level (more acidic)
When your soil’s pH level is over seven, the soil may be too alkaline. You may need to decrease its pH level and make it more acidic. There are two simple ways to decrease your soil’s pH level: adding elemental sulfur or adding organic matter
Adding Elemental Sulfur
You can find elemental sulfur in almost any garden store, making it highly accessible. Unlike what you may normally hear in the news about sulfur, this element is an essential ingredient for many plant’s health.
This soil is too firm and dry for the sulfur, image from Nature's Lawn and Garden, Inc.
Application: You want to have loose and moist soil before applying elemental sulfur. Loosen the soil with a spade or your hands if the soil is too hard and water the soil. Then lightly add the elemental sulfur to the soil. You do not need much, as little as one tablespoon for every four inch (ten centimeter) square is enough.
Note: Elemental sulfur is also known as flowers of sulfur, or aluminum sulfate
Adding Organic Matter
Organic matter is decaying plant or animal material, can come in many different ways. The three common forms of organic matter are compost, manure, and tree leaves. You may find these in garden stores or your local farms.
Wood bark is another example of organic matter, image from Harvest to Table
Application: Spread enough organic matter on the soil to partially cover the top layer of the soil. If you are in a colder season, like fall, you can leave the organic matter to protect the soil from frost. If not, then mix the organic matter with the soil.
These are a couple simple ways you can decrease your soil’s pH level. After applying either of these techniques, remember to test your soil again after three to six months.
Want to learn more about soil? Here are a few other articles for you!
- Testing your soil with vinegar and baking soda
- Testing your soil with cabbage (coming soon!)
- Ideal plants to grow by soil pH level
Header image by Neslihan Gunaydin