
Lawn Fertilizer Guide
Owning a lawn requires a certain degree of regular upkeep to keep it looking healthy and green. I learned quickly as a new homeowner that proper, regular watering and cutting truly does take care of the majority of your grass needs, but to ensure healthy roots and plant longevity, fertilizer is a crucial component.
Depending on where you live and types of grasses you have planted, your lawn will have specific needs at different time of the year. Applying the correct fertilizer schedule for your lawn can take a green, grassy yard and turn it into a thick, carpeted area your whole family will enjoy.
If this sounds a bit overwhelming, especially if you have ventured into the world of fertilizers and have been assaulted by the incredibly array of choices offered surrounding nutrient content, application processes, and seasonal mixes- no worries, as I’m here today to help break all this down so you can approach your lawn care with a bit more information.
Content
- Introduction
- Why Does my Lawn Need to Be Fertilized?
- What is Lawn Fertilizer?
- Does Lawn Fertilizer Expire?
- Lawn Fertilizer Nutrients
- Lawn Fertilizer Numbers Explained
- How to Choose the Nutrients Needed for Your Lawn
- Lawn Fertilizer Types
- Is Lawn Fertilizer Harmful?
- How to Apply Lawn Fertilizer
- Fertilizer Burn
- Lawn Fertilizer Schedule
- Lawn Fertilizer Tips
- Conclusion
Like all living things, your lawn requires food. The roots of your grass take up the nutrients (vitamins and minerals) found within the soils as they come in contact with them and release them to the vegetation in order to grow. Each fall, as the temperatures begin to drop, the leafy part of your plant sends whatever nutrients it has gotten from the sun and stores it back into the roots for the following spring’s growth.
Unfortunately plants generally use more nutrients than what are naturally available from both storage and soils to look as lush and healthy as you may want it to be. This is especially true of non native grasses that have been hybridized to basically be a living carpet for your yard. Therefore, applying fertilizer properly helps reintroduce essential nutrients back into the soils for your grass to utilize it in its growth.



Lawn fertilizer is available in either a granular or liquid form which is what makes up the substrate within which the nutrients are held for release into your soils. Basically, fertilizer is food for your lawn to help add additional nutrients for the plant use that may be missing from the soils, or are not in enough abundance to get the results you want.
Fertilizer can come in slow release and quick release versions, as well as have specific nutrient content for your types of grass. It also can be mixed especially for certain times of year. It may also have weed or insect control added in as well, so it’s important to know a bit about your lawn before deciding what kind of fertilizer you may need. For example, it doesn’t hurt to know:
- What types of grass do you have?
- Is it a cold season or warm season grass?
- What are the watering requirements?
This isn’t difficult to figure out as there are many available online identification guides that explain the grasses and what their requirements are. In fact, many fertilizer companies have guides offered online as well to help you choose the best fertilizer for your specific lawn type.
You also may want to take into account what type of soils you have. If you laid turf over caliche (a hard packed, nutrient deprived soil), then you will need to be providing the majority of nutrients to your grass to keep it growing until it begins to produce its own. This is also true of sandy soils that often leech, or allow nutrients to pass through quickly.
The short of this is no, fertilizer, if stored correctly, truly doesn’t expire. Fertilizer should be stored in a cool, dry environment. Granular fertilizers will absorb moisture in humid conditions and form hard, rock like clumps, but as long as they haven’t been soaked and allowed to drain, then your nutrients haven’t been lost and all you have to do it break it up with a hammer.
Liquid fertilizers will settle and will need to be shaken well before application, but will be just as good as if they were new.

All plants need three primary nutrients in order to grow and thrive. These are nitrogen, phosphorus, and potassium. Nitrogen is associated with leafy, green growth and also helps protect heal against insect or disease attack.
Phosphorus helps transfer energy from the roots to the leaves, and vise versa. It also helps promote additional root development, which is important since roots are what is needed to sustain healthy growth. Potassium helps with how water is used by the plant and determines how well it deals with stress.
These nutrients are found in all fertilizers and are represented by the three numbers you often can find on the front of the fertilizer packaging. These numbers are the percentages of each nutrient found within the bag and are called the fertilizer grade. Depending upon what nutrients your lawn, or soils, are lacking will help you decide which nutrients you need most of.
The numbers are always found in the same order and reflect nitrogen, phosphorus, and potassium nutrient levels. To provide an example, a 50 lb bag may have the number 10-10-10 marked upon it. To determine exactly how many pounds of the nutrient are within the bag, you simply multiple 50 by .10, which equals 5. Therefore there is 5 pounds of each nitrogen, phosphorus, and potassium within the bag which will be evenly distributed.
You should address fertilizing as feeding your soils, rather than feeding your plants (although liquid fertilizers CAN feed your lawn directly, which we will get into later). Healthy soils equal healthy plants. Poor soils will reflect in your lawn not looking as healthy as you would expect. Plus, adding too much of one nutrient can also become problematic.
The best way to determine your soil needs is to run a quick soil test. This is especially true if you have been struggling with your lawn needs and have not been able to find much to work for you.
Although optional, these are often very inexpensive, or even free, and provide a nutrient breakdown of your soil sample to give you an idea of what you are lacking and will need to provide. Many times they are offered through your local extension services or USDA office. At the very least you have the information on hand if ever needed.
Slow Release
Granular
Organic
Weed Control
Seasonal
Quick Release
Liquid
Synthetic
Insect Control
Natural Applications

We are talking about safety in terms of your kids, pets like dogs and cats who roam the lawn and of course the environment. Since your lawn is truly an extension of your living area, the safety concerns surrounding the applications of certain fertilizers should be taken into consideration. If you have a company applying your fertilizers, then they most likely have some pretty strong disclaimers surrounding how they use their products for your own safety. Make sure to ask for written follow up instructions and for them to place signs on your lawn if it isn’t safe to be on for any amount of time after application to let your neighbors know as well.
Most fertilizers found in your local garden centers are marked as pet and kid safe after application and watering. This is a big difference compared to a decade ago when most fertilizer applications requires at least 48 hours or a watering of at least a quarter inch before lawn could be safety walked upon again. Fertilizer companies do mark their bags with occupational hazards of applying and use, so be sure to look over this in advance to make sure you have the safest product available for your family.
Even with safety measures in place, if you are still unsure of any chemical application, consider a more organic feed. Since these are made with natural products, they are often safe enough for accidental ingestion, in case you have a very curious pet. These may take a little longer to show results, but are very effective in the long run.
Liquid fertilizers can either be used with a setup that helps apply it over a large area, such as upon a four-wheeler, or with the use of backpack sprayer. These can get expensive, so if you plan on using liquid concentrations, make sure you are aware of the investment for proper application.
Smaller applications are available that hook into your hose and mix with the water. Liquid fertilizers have a higher incidence of lawn burn due to poor dilution, so it’s important to make sure your ratios to water are correct with fertilizer concentrations.
Granular fertilizers are more widely available in more nutrient options for a reason. To start the are more affordable, and they are also easier to spread. You can also more easily wash it out in the case of over fertilization.
Granular forms can be spread by hand, or with a push spreader that allows you to set your concentration levels. You should water your lawn lightly prior to application to help the fertilizer stay where it falls, and then you need to water well afterwards to help activate it and allow it to begin seeping into the soils where it will be accessible to the grassroots.

Fertilizer burn is one of the biggest concerns when working with fertilizer. This occurs when too much of a nutrient is applied to a specific area, the fertilizer is not allowed to properly soak into the soils, or the wrong fertilizer is applied for the season or grass type.
This problem looks just like it sounds, with either large areas, or smaller areas of lawn beginning to wilt and look brown and burnt within a few days after fertilizer application. One way to ensure that this doesn’t occur is to make sure you water properly after spreading fertilizer. If you happen to notice burn, then the before you write off those areas as a loss, just water heavily for at least a week to help dilute the nutrients and allow the roots to stay healthy and wet.
As explained above, your fertilizer schedule will be determined by the many variables you should consider before fertilization. The types of grasses you have and the health of your lawn should indicate the type of fertilizer you want to apply, and every company has their own detailed use of their products that helps to explain when and how to apply.
Once you have committed to a specific product, if you have liked your initial results, you should stick with that brand and follow their guidelines to a healthier lawn. Most companies have online resources to help you create a schedule that works best for you, and the product itself should come with detailed use instructions.
If you use a commercial company they will work with you concerning lawn needs, fertilizer choices, cost, and a schedule to take the guesswork out of doing it yourself.

Know your lawn type

Determine your lawn needs

Water your lawn lightly prior to fertilizing and allow grass to dry

Invest in a good spreader for even application

Apply fertilizer according to directions

Do not over fertilize to get quicker results

Water after application unless using vegetation uptake

Allow your grass clippings to sit on your lawn
Conclusion
Lawns require care to keep them growing and looking healthy. This almost always includes a fertilization schedule, and knowing your lawns and lawn needs is an important part of this process. However, fertilizing details can quickly get complicated if you are unsure of what type of lawn you have, its need, and exactly what you are looking at inthe fertilizer aisle at your local garden center.
Hopefully this lawn fertilizer guide has broken down the many details surrounding this maintenance step so you can approach fertilizer use with confidence. If you have any helpful fertilizer tips we would love to hear them below! Questions and comments are always welcome as well, and if you love it- please share!
Wow, this is definitely the most informative guide I have seen on fertilizer! I’ll be sharing this with our audience on social media and will use it as a reference in the future. Thanks for the hard work thats gone into this!
I personally live in an area of the UK where our grass is terrible, this has given me hope we can get our lawn to what it should be!
Thank you Kevin, good luck with your lawn!