Maintaining a healthy pH level is essential for the growth and survival of plants. Understanding what pH is, how it affects the health of your soil, and how to adjust it when necessary is arguably one of the most important and overlooked aspects of creating a thriving garden. In this article, we’ll delve into what pH is and how to use it to your gardening advantage. Ready?
pH is a measure of the acidity or alkalinity of a substance, and it stands for “potential of hydrogen.” The pH scale ranges from 0 to 14, with 7 being neutral. A pH below 7 indicates acidity, while a pH above 7 indicates alkalinity, which is a substance’s ability to resist acidification. The further the pH deviates from 7, the more acidic or alkaline the substance becomes.
But what does this mean for your plants?
The pH level of your soil plays a significant role in the health of your plants. If the pH is too high or too low, it can cause nutrient deficiencies, which can lead to stunted growth, yellowing leaves, and reduced yields. Soil pH also affects the activity of microorganisms in the soil, which play a crucial role in breaking down organic matter and releasing nutrients for plant uptake. In short, pH affects the availability and consumption of nutrients to plants.
What’s tricky about pH is that there isn’t a one size fits all approach. While most plants prefer slightly acidic soil, with a pH between 6 and 7, others will have more acidic or alkaline preferences. Regardless, having an understanding of this preference among your plants is important because pH impacts the availability of nutrients like nitrogen, phosphorus, and potassium, which are vital for healthy growth.
While pH may seem a bit nebulous, measuring it has become incredibly easy in recent years. In fact, measuring it is basically just a matter of spending about $10-20 on a soil tester, like this one here.
Once you have one, you can begin testing the pH of your soil and make adjustments depending on plants’ preferences accordingly. While testing the pH is basically as easy as sticking the meter in the soil and reading the gauge, there are two important things to keep in mind: 1) pH can vary at different parts of your garden, so be sure to take multiple readings, and 2) pH can also change throughout the course of the year, depending on the weather. It’s good practice to test at the beginning of each season.
Now that we have an understanding of how pH affects plants, let’s take a look at how to raise and lower it so your plants can thrive.
What to do if your pH is too high?
If your soil pH is too high (which means it’s too alkaline), you can lower it by adding sulfur or an acidifying fertilizer. Sulfur reacts with water in the soil to form sulfuric acid, which lowers the pH. Acidifying fertilizers also can contain ammonium nitrate or ammonium sulfate, which acidify the soil as they break down. When tweaking pH, it’s essential to follow the instructions on the product label and retest the pH after a few weeks to ensure you don’t overcorrect.
What to do if your pH is too low?
If your soil pH is too low (which means it’s too acidic), you can raise it by adding lime or wood ash. The lime reacts with the soil to neutralize acidity, while wood ash contains calcium carbonate, which acts as a natural liming agent. It’s important to note that adding too much lime can make the soil too alkaline, so it’s best to add small amounts at a time and retest the pH after a few weeks.
Keep in mind, that ideal soil for one plant may not be ideal soil for another, so be sure to keep track of the preferred pH range of your plants and adjust the soil accordingly. By testing your soil pH, making adjustments as needed, and taking a holistic approach to soil health, your dream garden is closer than you might think.