Lawn Fertilizers 101: How To Achieve Green Grass

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Lawn maintenance can feel daunting at times. It is especially true for new homeowners looking to improve or take care of their lawns.

When it comes to proper lawn maintenance and care, lawn fertilization plays a significant role. However, this raises many more questions for new homeowners. 

Such as how to know what lawn fertilizer to use. If you are wondering what lawn fertilizer you should opt for to have a green lawn all year long, you’ve come to the right place!

By the end of this article, you will have a clear grasp of lawn fertilization and how to apply lawn fertilizer.

Fertilizer pellets spraying from spreader

Why Do Your Lawns Need Fertilizers?

Nutrients are essential for all living organisms to thrive. It is also true for plants, such as lawn grass.

However, it is difficult for plants to gather all the necessary nutrients they need to grow from their environment.

And that is why fertilizers play such an important role. There are three nutrients essential for the healthy growth of plants.

These are potassium, phosphorus, and nitrogen. Compared to other plant nutrients, plants need these in large quantities.

Among these three, nitrogen plays an essential role as it is the primary nutrient behind the growth of healthy, leafy plants.

So, when it comes to maintaining a luscious green lawn, nitrogen is necessary, more so than for other plants.

However, among the three, nitrogen is the least readily available. Phosphorus and potassium are generally easily obtainable in healthy lawns as they are immobile in soil.

But nitrogen, on the other hand, gets swept away with irrigation or rain. Thus, unlike the other two, nitrogen must be replaced frequently to keep your lawn healthy.

As a result, fertilization is necessary to maintain a healthy green lawn. When looking at a high-quality fertilizer, you will notice that the first number of the N-P-K ratio is the highest.

It signifies the amount of nitrogen, phosphorus, and potassium present. 

Different Types Of Lawn Fertilizer

The types of lawn fertilizer available on the market vary for different reasons—synthetic, organic, release period, etc.

So, let us get a basic idea about the other fertilizers available.

Granular Lawn Fertilizers

Granular fertilizer may be either slow-release or time-release. Time-release fertilizers are suitable for application over many months.

Thus, not requiring the gardener to remember to fertilize the garden at fixed intervals.

However, slow-release fertilizer releases nutrients to the roots slowly. As a result, it prevents it from getting leached away and makes it easy to apply. Furthermore, it lowers the risk of burning the lawn.

This type of fertilizer comes in tiny granules sold in bags. And it is popular due to its ease of application.

The application involves using a fertilizer spreader. Furthermore, you do not need to dilute or mix them with water making their application very straightforward.

Liquid Lawn Fertilizers

Another common type of lawn fertilizer is liquid fertilizer. Which comes in various forms; some require dilution with water before use as they come in concentrated bottles.

In contrast, others come in ready-to-spray bottles that you can connect to your garden hose. 

Compared to their granular counterparts, they are fast-acting and give your lawn faster green-ups. But it does not last as long as granular fertilizer.

Additionally, it results in patchier coverage and has a higher risk of burning the grass than granular fertilizers.

Synthetic Lawn Fertilizers

This chemical fertilizer offers quick greening and an instant release of nutrients into the soil. But, it is harmful to the environment as it can pollute the water after being washed away by rainwater.

Furthermore, synthetic fertilizers focus more on the plant’s health than the soil’s health.

As a result, synthetic fertilizers can hurt the organisms in the soil. These organisms can often be beneficial for the growth of plants, such as good bacteria and earthworms. 

But, despite these downsides, synthetic fertilizers are still in use because they are cheaper and provide faster outcomes than organic fertilizers.

Organic Lawn Fertilizers

Organic fertilizer, as the name suggests, is organic. It constitutes the byproducts of living organisms or the remains of living organisms.

These include bonemeal, seaweed, cottonseed meal, compost, and manure. 

Unlike its synthetic counterpart, it is good for the environment and focuses more on the health of the soil than the plant.

Thus, promoting biodiversity in the soil by making it more habitable for good bacteria and earthworms. 

Furthermore, organic fertilizers enrich the soil structure and are safe for pets to be on, even right after application.

It is a long-term solution to your plant’s nutrient needs, whereas synthetic fertilizer is a short-term solution and requires frequent reapplication.

However, it still has its downsides, being more expensive than the chemical variety. Additionally, it takes longer to show visible benefits as it focuses more on soil health.

You will need to apply it on several occasions to get significant results.

How To Know What Lawn Fertilizer To Use?

Before fertilizing your garden, let us figure out which fertilizer to use on your specific lawn.

For that, you need to understand the numbers on the bag and correlate these numbers with your lawn’s needs using a soil test.  

What Do The Numbers Mean?

When looking at any bag of fertilizer, you should notice a combination of three numbers. They will usually be in an assortment of 16-4-8, 32-0-10, 10-10-10, or something similar.

This combination of numbers is the N-P-K ratio of the fertilizer. It is crucial when picking the right fertilizer for your lawn.

As I mentioned earlier, N-P-K stands for nitrogen, phosphorus, and potassium. These are the essential nutrients for the healthy growth of a green lawn.

And these dictate how much of each nutrient is present in your fertilizer. For example, a fertilizer with an N-P-K ratio of 10-10-10 means that it has 10% of each of the three nutrients.

You can later use this percentage to calculate how many pounds of each nutrient are present. Just multiply the rate by the bag’s total weight. 

Each of these three nutrients plays a role in the growth of your lawn. Potassium boosts the plant’s disease resistance and health of the plant.

On the other hand, phosphorus promotes the development of more robust roots. Lastly, nitrogen improves the green color of grass as well as promotes faster growth.

Thus, fertilizers with a high nitrogen ratio can be a game changer for those looking for a greener and faster-growing lawn. But before making any rash decisions, I recommend performing a soil test.

It will give you an idea of what exactly your lawn needs.

Taking A Soil Test

Firstly before even being able to test your soil for nutrients and more, you will need to take a soil sample. For this, you will need a clean hand towel, a plastic buck, and a shovel.

Ensure they are all clean and have no rust that can contaminate the soil and hamper the results.

Afterward, collect soil from a few different spots in your lawn so you can get a better idea of what your lawn needs.

It is more noteworthy if the grass is visibly different in some areas compared to others, making it necessary to take multiple samples.

Additionally, ensure that the samples are taken from areas that have not been fertilized. As a result, your test will show you what nutrients your soil lacks.

When digging, make sure the hole is at least six inches deep. Mix the dirt at the bottom, take around a cup of dirt, and collect it in your bucket. 

Whether you use an at-home kit or send it to a lab, follow the instructions. As at-home kits differ, it is best to follow the instructions provided by your specific kit for testing.

After taking the test, you should be able to see what nutrients your soil has, what it lacks, and maybe even the pH level; this allows you to pick a fertilizer that best fits your needs.

Fertilizing Your Lawn

Now that you know how to pick the right fertilizer for your lawn, let’s look at when you should apply them and how to use them.

Start By Checking The Soil Temperature

When fertilizing your lawn, you should start with soil temperature. Spring is the ideal time to use fertilizer on your lawn when the soil temperature is around 55 degrees Fahrenheit.

An excellent way for you to be able to tell this is by noticing the grass beginning to grow as well as lilacs blooming. 

You can also use a soil thermometer to measure the temperature. It is the ideal temperature if you are planning to use fertilizer.

So, mid-April should be the best time to start fertilizing your new lawn.

Using Slow-Release Fertilizers

Between the different types of fertilizers, I highly recommend using slow-release fertilizers. These take longer to release their nutrients into the soil entirely.

Thus, allowing you to take much more significant gaps between applications. As a result, you’ll fertilize less frequently, saving you both money and time. 

Though you can get a better idea of what nutrients your lawn needs through the soil test, I recommend using a slow-release fertilizer with a high nitrogen value, as it will promote growth and keep your lawn nice and green.

However, do not overdo it, as it could lead to your lawn overgrowing, and you will have to mow it more frequently.

A dose of two to three pounds of nitrogen over a complete season is ideal; as a result, you can get the best result.

You can calculate how much that is with the help of the N-P-K ratio on your fertilizer bag.

Planning For Future Application

Once you begin the fertilization process, you should plan for the future. The best is to prepare for a total of 5 different applications starting with April.

As mentioned earlier, the first feeding should occur in April when the soil temperature is ideal. 

After that, you can follow up with the second feeding around four weeks after the first application. It should be around mid-May if you did the first feeding in mid-April when the soil temperature should be perfect. 

As we advance from here, you need to fertilize every six-eight weeks till October. For the third feeding, I highly recommend choosing organic fertilizer to promote the biodiversity of the soil and strengthen its soil structure. 

Fall fertilization is crucial because the grass grows even in the fall, and the roots need fertilizer as they go deeper into the ground.

Switching to a fertilizer with a high quantity of phosphorus and potassium would be best to promote root growth and strength.

Water And Fertilization

Finishing up on this topic, I have to talk about the importance of watering your lawn when it comes to fertilization.

Even though some people believe that the more you water your lawn, the less fertilizer you will need, the opposite is true.

More water promotes the growth of grass on your lawn. It results in more fertilizer to provide the necessary nutrients for this grass to thrive. 

Those of you who own automatic sprinklers need to fertilize every six weeks. On the other hand, those who do not must wait an additional two weeks to fertilize again.

Please read the fertilizer instructions thoroughly, as some fertilizers may come with instructions about when to water your lawn or before applying the fertilizer.

Each fertilizer has its requirements; some may require you to soak the lawn thoroughly before application. 

For example, granulated fertilizer slowly releases nutrients into the soil. But they do need some moisture to help with the process of breaking down.

Do Not Overfeed Your Lawn

Over-fertilization is a common issue for lawns. Almost all fertilizers come with a recommended rate of application.

However, I recommend starting out using only half of that rate for the best results. As for fertilization, it is better to apply less than overfeed your lawn.

Furthermore, you should check the weather forecast before applying your fertilizers, as a downpour can result in all your hard work being washed away.

Then that necessitates another reapplication, and you will have a more challenging time not overfeeding your lawn in that scenario.

Special Types Of Fertilizer

Other than the most typical types of fertilizers, there are some unique varieties to meet needs that regular fertilizers cannot.

New Lawn Fertilizers

A lawn starter fertilizer is something to simplify life for those who have planted new sod or grass. Specifically designed for fresh grass, this fertilizer can ensure the longevity of your new lawn.

It contains a high quantity of phosphorus to strengthen and help the growth of roots while having a lower amount of nitrogen to prevent burns.

Weed Preventive Fertilizers

Some fertilizers contain post-emergent or pre-emergent herbicides. These work to counteract the growth of weeds in your lawn while helping provide grass nutrition. 

The post-emergent varieties deal with already present weeds in your lawn and work to kill them. In comparison, the pre-emergent type prevents the growth of weeds altogether.

By applying them in early spring, you can avoid crabgrass and other varieties of summer weeds.

Seasonal Lawn Fertilizers

Lastly, there are seasonal varieties of fertilizer. These are designed to meet the seasonal requirements for your lawn.

Thus, you can not use the same fertilizer for each application. Thus, requiring you to buy a new fertilizer for each season. 

As I mentioned earlier, autumn fertilization is crucial for the healthy growth of your lawn. Thus, using a summer fertilizer during that crucial period can lead to severe problems down the line. So, be sure to fertilize your lawn accordingly .

When it comes to spring fertilizer, you should check the N-P-K ratios to ensure that the amount of nitrogen is not that high.

It is ideal for the N ratio to be ten or less than ten, lowering the risk of burning after a long winter slumber. Additionally, potassium and phosphorus can play a vital role in its growth after winter.

In the case of summer fertilizers, the N ratio should be 20 or higher. It needs more nitrogen during this time to keep it green and healthy through the harsh summer heat.

Fall is the most crucial season as your lawn must prepare for winter. As a result, your lawn needs less nitrogen and lots of potassium and phosphorus to survive the cold winter.

The N value is ten or less than ten, while the other two values must be higher than the N value of N-P-K.

When is the best time to apply lawn fertilizer for achieving green grass?

The best time to apply fertilizer for achieving green grass is in early spring, when the soil temperature reaches around 55 degrees Fahrenheit. This allows the grass to begin actively growing and allows the fertilizer to be absorbed effectively, resulting in a healthy and vibrant lawn.

Final Thoughts on Knowing What Lawn Fertilizer to Use

The upkeep of a lawn can prove to be quite a daunting task. Especially considering how complicated the entire process can seem to a new homeowner.

From understanding the numbers on the fertilizer bag to how to feed your lawn according to its needs properly, it can get confusing.

Thus, I hope this article gave you a sneak peek into the secrets of lawn fertilization. And how to know what lawn fertilizer to use. Goodbye and Goodluck!