What Is The Best Ratio For Lawn Fertilizer?

What Is The Best Ratio For Lawn Fertilizer

Every lawn needs a specific ratio of fertilizer to maximize its potential. This ratio is typically made up of a combination of several vital ingredients; Nitrogen, Potassium, and Phosphorus. Each chemical provides a key element to your lawn.

It might not sound obvious, and we’re here to help. There is something similar to an exact science to ensure you grow the best grass in the neighborhood (or cul-de-sac, if you will). Intimidating? Maybe. Impossible? Definitely not. 

What Is A Good Fertilizer Blend For Lawns?

There is a good fertilizer blend for each lawn. The good news is that the same ratio can be applied to a majority of lawns. It is always good to evaluate your soil accurately with a soil testing kit (what an original name). 

Let’s start with the basics; what even is a fertilizer blend? Fertilizer blend means the ratio of nitrogen, phosphorus, and potassium, otherwise known as an NPK ratio. Each chemical plays a large part in the health of your lawn. For most lawns, the ideal ratio is 4:1:2 or 3:1:3. 

It might feel like we’re throwing random numbers at you, but we promise, we’re not. To better understand why each chemical is so important, let’s dive deeper.

When Is The Best Time To Apply Fertilizer?

Early spring is the most effective time of year when it comes to applying fertilizer. This is because many grass types are in their peak growing cycle and get the most out of the fertilizer. That being said, spring isn’t the only time you can apply fertilizer. If preferred, a winterized fertilizer can be applied in the fall and will still be as effective.

What Do The Numbers Mean On Lawn Fertilizer Bags?

Scotts Turf Builder Weed and Feed 3; Covers up to 5,000 Sq. Ft., Fertilizer, 14.29 lbs.

Three different numbers are found on the fertilizer labels, each standing for a different element. The first being nitrogen, the second phosphorus, and the last, potassium. These are the primary nutrients found in the fertilizer. For example, if the ratio is 4:1:2, there is 4% nitrogen, 1% phosphorus, and 2% potassium.

As a general rule, use 1 pound of nitrogen per 1,000 square feet of lawn. A soil test kit comes in handy to determine how much of each chemical you should use. Soil test kits can be found at most local gardening stores. 

In most cases, nitrogen is one of the most important numbers to pay attention to when selecting a fertilizer, as it is critical for growth. This is not always the case, so we would recommend testing the ground to determine what minerals it lacks.  

Why Is Nitrogen Important?

Nitrogen is arguably the most crucial element when it comes to healthy grass. To better understand the importance of nitrogen, let’s take a look at why it is essential for growth.

What Nitrogen Does For Your Grass

To grow, grass has to be able to go through the process of photosynthesis. Nitrogen allows grass to produce chlorophyll, which, you guessed it, is necessary for photosynthesis to occur. Simply put, Nitrogen promotes rapid development and the note-worthy green color in the grass.  

The Different Types Of Nitrogen

Green Grass

There are two significant types of nitrogen, slow-release, and fast-release. There are pros and cons to both types of nitrogen. To determine what type of nitrogen is in the fertilizer you have, refer to the back of the bag. 

  • Fast-release – The pros of fast-release nitrogen are in the name. Nitrogen is immediately supplied to the grass, resulting in rapid growth and color change. While this sounds wonderful, it tends to go just as quickly as it comes, making it best for short-term solutions. Because nitrogen promotes rapid development, fast-release nitrogen can cause the grass to become weak and susceptible to disease.
  • Slow-release – In most cases, slow-release nitrogen is the answer. It is released gradually to the grass, allowing the plant sufficient time to use the nitrogen effectively. That being said, this process requires patience (arguably the most challenging part). The upside is that the results last much longer, as the grass is not put under stress.

Signs Of Nitrogen Deficiency 

Knowing the different signs of deficiency is essential because nitrogen is an essential part of healthy grass. Not sure where to start? Here are a few different warning signs your grass requires more nitrogen. 

  • Little to no growth
  • Weak, yellow patches
  • Thin blades
  • Pale to yellow-green

Why is Phosphorus Important?

Next in line is phosphorus. First of all, if you can even spell the word, we’re very proud. As with nitrogen, it also plays an important role in healthy grass.

What Does Phosphorus Do For Your Grass

Phosphorus is important for the early stage of grass’s lifecycle. Phosphorus is responsible for cultivating new tissue and cell division. Developing a strong root system will determine the hardiness of the grass moving forward, so it’s crucial to have phosphorus dense soil right from the beginning. As the grass develops a robust root system, the importance of phosphorus decreases.

Signs Of Phosphorus Deficiency

Now that we know the importance of the chemical, how do you tell if your grass has a phosphorus imbalance? Here are a few signs;

  • Stunted growth
  • Abnormal deep green color
  • Reddish purple color

Why is Potassium Important?

Green Lawn

Congratulations, you’ve made it to the “K” in NPK. We must say, you’re just about qualified to teach environmental science. If we’re being honest, Potassium does a little bit of everything (perhaps an overachiever). Let’s dive in.

What Does Potassium Do For Your Grass

Potassium does the upkeep of the work nitrogen and phosphorus have already completed. Within the plant’s tissue, potassium regulates the water, nutrients, and carbohydrates the grass receives. Potassium improves the strength and builds the drought resistance of the roots. It also helps regulate energy to prevent excessive energy loss. Because of its ability to control, it aids in disease and cold resistance. 

Signs Of Potassium Deficiency 

Now that we know just how vital potassium is when it comes to the overall upkeep of grass, it is easier to spot the deficiencies. Here are a few key things to look out for;

  • Wilted, drooping appearance
  • Increased sensitivity to changing temperatures
  • Blotchy patches