The Connection Between Lawn Fertilization & Soil pH

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The health of your lawn depends on many factors, and one of the most important is soil pH. The pH level of your soil affects how well nutrients are absorbed by the plants, which in turn impacts their growth and health. But did you know that fertilizing your lawn can also have an effect on soil pH? This guide will discuss how fertilizers affect soil pH levels, as well as what can be done to adjust them when necessary. Read on to learn more about the connection between lawn fertilization and soil pH!

What Is Soil pH?

pH scale

Soil pH is a measurement of the acidity or alkalinity of your soil. The pH scale runs from 0 to 14, with 6 to 7 being neutral. Anything below 7 is considered acidic, while anything above 7 is alkaline. Different plants and soil types prefer different levels of pH for optimal growth, and it can be difficult to know what level you’re at without testing your soil.

The letters "pH" stand for potential of hydrogen or power of hydrogen (translated from Latin). The pH scale measures the activity of hydrogen ions in the soil and helps us figure out if it's acid or alkaline on the 0 to 14 scale mentioned above. Knowing this information can help gardeners and lawn care enthusiasts make the right choices when it comes to picking fertilizers and applying products in their yards.

How Do Lawn Fertilizers Affect Soil pH?

npk for the soil

Most lawn fertilizers are formulated with a balance of nitrogen, phosphorus, and potassium (NPK) that helps promote healthy grass growth. However, some types of fertilizer contain additional ingredients such as sulfur or iron, which can help adjust the acidity or alkalinity of your soil. These additives work by releasing ions into the ground that react with existing minerals in order to raise or lower the overall pH level. This means that if you choose a fertilizer with additional ingredients like these, then you may need to keep an eye on its effects on your soil and adjust its pH if necessary.

It's also important to note that improper pH levels affect your lawn's ability to absorb nutrients. When fertilizers are applied to a lawn with a pH level that is either too high or too low, that lawn is not able to fully absorb those nutrients into the soil. Fertilizing a lawn that is not within healthy pH levels could damage grass growth, which is why adjusting pH levels when necessary is so important for your fertilization treatments.

Healthy pH Levels For Your Lawn

pH meter

The pH levels of your soil can have a significant impact on the health and growth of your lawn. Different types of grasses thrive in different ranges, so it is important to know what the ideal range for each type is before fertilizing or adjusting any levels.

For cool-season grasses such as Kentucky bluegrass and fescue, a slightly acidic soil ranging between 6.0 and 7.0 is best for optimal growth. These species prefer soils with high organic matter content and are tolerant of low-fertility soils if they remain within that range. Warm-season grasses like Bermudagrass and Zoysiagrass require higher alkaline conditions than their cool-season counterparts, and they grow best in a pH range from 5.8 to 7.5, though some varieties may need even more alkalinity depending on their location and climate preferences. Soils with lower nutrient availability often require higher pH levels to promote strong root development in warm-season grasses.

How To Raise Soil pH When Fertilizing

lime added to soil

Adding lime to your lawn is one of the most common ways to raise soil pH when fertilizing. Lime, or calcium carbonate, is a natural substance that can be used to adjust the acidity of soils and make them more alkaline. It works by releasing calcium ions into the soil which react with other minerals in order to raise the overall pH level. This makes it an ideal choice for gardeners and lawn care enthusiasts who want to adjust their soil's pH levels without using harsh chemicals or additives.

  • REMEMBER! While adding NPK fertilizers is a necessary part of proper lawn care, the chemicals present in these products do actually make your lawn's soil more acidic. This means that lime can and should be applied to your lawn every time you fertilize in order to maintain the proper pH balance and ensure optimal growth.

How To Lower Soil pH When Fertilizing

liquid fertilizer spreader

If your soil's pH level is too high, then it may be necessary to adjust it by adding sulfur or an aluminum sulfate-based product to your lawn. Sulfur works by releasing hydrogen ions into the ground which react with other minerals in order to lower the overall pH level (just like lime, but in the opposite direction of the scale). It's important to note that this process takes more time, as the ions must move through the soil before they start affecting the acidity levels, so you may need to wait a few days for the effects of your treatment to take hold.

  • REMEMBER! Sulfuric acid is a fast-acting option for lowering pH, but it is dangerous if applied improperly. It is not recommended for use by non-professional lawn care. Look for elemental sulfur products for the safest and most eco-friendly option!

Get Your Soil Tested!

Testing Your Soil

Before making any adjustments to your lawn's pH levels, it is important to get a soil test. Professional lawn care services will be able to give you an accurate assessment of your soil's acidity or alkalinity as well as the type of grass that would be best suited for it. This way, you can make sure that any fertilizer you apply is tailored specifically to your particular needs and that it won't have any adverse effects on your lawn's health.

At-home testing kits are available, but you always run the risk of improperly reading or applying them and potentially damaging your lawn. To avoid such mistakes and give your soil the best treatments possible, call a local lawn care provider like Brothers here in Louisiana! We will get those pH levels right and ready to give you the lawn of your dreams!