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What are the numbers on fertilizer? What are the different types of grass?

What Are The Numbers On Fertilizer? What Are The Different Types Of Grass?


With so many different fertilizers out there and so many different grasses, its no wonder there is so much confusion. Believe it or not each fertilizer out there as similar as they might be has been designed to serve a particular need. Lets understand what the numbers mean and then lets learn about grasses.


N= Nitrogen   Nitrogen is the first number and it is used to green your lawn and plants. Nitrogen is needed in different amounts at different times of the year depending on the grass. It is one of the most essential nutrients of the 12 essential nutrients needed by plants and 1 of the 3 macro nutrients. Warm season grasses need more Nitrogen when it is warm and none when dormant and cool season grasses require more when it it cool. Premium lawn food is high in nitrogen, which is used to feed established lawns in their peak season (28-4-3)


P= Phosphorus  Phosphorus is the middle number which is essential for root development and creating blooms. This is a key element in helping with the development of root systems of newly seeded grass and plants. Phosphorus is the key ingredient in starter fertilizer and root stimulators (18-24-12).


K= Potassium  Potassium is used for winter hardiness and it helps a plant survive through the cold season. It helps plants and grass develop a deeper root system, keeping the plant more insulated. You will notice that a winterizer fertilizer will have an elevated amount of K.

Grass seeds come in many different sizes, therefore application rates vary drastically from seed to seed. Many seeds (centipede and zoysia) come as seed and mulch simply because the seed is too fine to get proper coverage with. Mulches or fillers are used to help get proper coverage.


Fescue is a cool season grass that thrives in the cool or cold weather and struggles in extreme heat. Fescue does not need much N in the the summer because it just wants to survive the heat (90 degrees and above). Too much nitrogen forces Fescue to have to look for nutrients for all the new growth which just stresses it out. When it is hot, what your Fescue needs is a plenty of water. Watering it early in the morning is ideal, as it is with all turf grasses, for this will help reduce risk of disease.

When starting your seed, it is recommended that you put down a starter fertilizer or some 10-10-10. This fertilizer balances N with P to help the roots work with the shoots. The best time to throw down Fescue seed is in the fall, therefore it has time to get established before the heat arrives. Spring is also a good time but fall is ideal. Fescue grass seed may say "drought tolerant" that is a lie. There is no such thing as drought tolerant Fescue, only Fescue that is more drought tolerant then others. Fescue does not spread, therefore overseeding is required every few years.

You will want to use 10 lbs of fescue seed per 1,000 square foot if you are starting fresh. If you are overseeding a lawn and just want to thicken it up then use 5 lbs per 1,000 square foot.

 fescue img.JPG

Bermuda Is a warm season grass that turns brown or goes dormant if the fall and winter. Bermuda seed likes starter fertilizer for the same reasons as Fescue but  Bermuda seed needs to be put down in the beginning of summer (June 1st), when it is hot. Bermuda has no trouble with nitrogen in the spring or summer. Bermuda grass has good drought tolerance, but would still prefer to be watered regularly. Bermuda does not need to be fertilized when dormant. Bermuda is an aggressive, spreading grass that is great at repairing itself if needed but can crawl into places you don't want it to if not managed properly.

Because Bermuda sod is an aggressive spreading grass and a hybrid, there is never a need to overseed it. Bermuda seed is great for seeding a bare area with full sun when sod is simply not in the budget. Read article below for why not to overseed Hybrid Bermuda sod.

Plant 1 to 1.5 lbs of uncoated Bermuda seed or 2 to 3 lbs of coated Bermuda seed per 1,000 square foot.

Check out the difference between common Bermuda seed and Hybrid sod.

bermuda img.JPG


Zoysia, is just like Bermuda, without the drought tolerance. Many varieties of Hybrid Zoysia has some of the best shade tolerance of most grasses. Established hybrid zoysia sod spreads well and does not require overseeding for the same reason as hybrid Bermuda sod.

Scotts 5 lb bag of zoysia seed and mulch will cover 1,000 to 2,000 square foot.


Centipede Grass doesn't need much food and although it prefers sun, it has pretty good shade tolerance. Centipede is different because it does not like Phosphorus, therefore we do not use starter fertilizer when seeding it. Your typical Centipede fertilizer is 15-0-15. It is also a spreading, warm season grass that goes dormant when it gets cold just like Zoysia and Bermuda. It thrives in acidic soil (4.5 to 5.5) and therefore grows well under pine trees which acidify soil. Centipede also does not need to be fertilized when dormant.

Scotts 5 lb bag of centipede seed and mulch will cover 1,000 to 2,000 square foot.

 centipede img.JPG

I am going to ask my Cali. crew to expound on St. Augustine grass and my Chicago crew to expound on Bahia and Kentucky Blue grass, for they are certainly the pro's with that.

Other Related Articles:

The Best Pasture Grass For Cows and Horses

12 Essential Nutrients Plants Need To Stay Healthy

What is lime and why is it important?

Vigoro Lawn schedule

How much water does my lawn need

Top Benefits of Leveling Your Lawn

Why did the weed and feed not kill my weeds?


Lawn Disease Control

Amending Different soil types
Not what you were looking for ? Try posting a question
Posted 2011-02-17T20:29:08+0000  by Ingar_HD_ATL Ingar_HD_ATL

Hello all. Hortman here in the Chicago area.

Kudos to greengiant for his excellent information on warm season grasses

and the cool season fescue grass. Here in the northern tier of the country we

use three major cool season grasses: Kentucky bluegrass, perennial ryegrass, and fescue.


Kentucky bluegrass is your classic “barefoot” grass. It is slow growing, shallow rooted, and

spreads by underground stems called rhizomes. This makes it very self-repairing and persistent. On the other hand it is a high maintenance grass. It has a low tolerance to heat, is moderately drought tolerant, and doesn’t do well with shade or high traffic. Also it is not very tolerant of insects and disease. You can tell it is Kentucky bluegrass by its boat shaped tip.


Perennial ryegrass is a clump type grass. It doesn’t spread, the clumps just get bigger.

It is fast growing and deep rooted. These features make it excellent for erosion control

on steep slopes. As a turfgrass it has a higher tolerance to heat than bluegrass, is moderately

drought tolerant, and has a high tolerance of insects, disease, and high traffic.


Creeping red fescue is the third of the trio of cool season grasses. It has a higher drought

tolerance than either bluegrass or ryegrass. But where it shines is in heavy shade. It can

handle only 2-4 hours of sun a day.


All three of these grasses can stand alone, but work best as a blend of all three. Their strengths overcome the weaknesses of each other. In establishment, the ryegrass and fescue will germinate and grow quickly to set things up for the bluegrass to come in later. In the heat of the summer the bluegrass can almost go dormant and have disease and insect problems. This is where the ryegrass shines with its resistance to insects, disease, and traffic. Meanwhile, the fescue quietly keeps looking good in the shade. All three use the same starter fertilizer (18-24-12) and peak season (28-4-3) as the warm season grasses.


While greengiant talked about what the numbers meant nutrient-wise, I’m going to talk

about what they mean mathematically. Each of the numbers on that fertilizer bag is the

percentage-by-weight of that nutrient in the bag. To make the math simple I’ll use

a bag of (10-10-10) all purpose. In a 10lb bag, each nutrient has 10% by weight or

one pound in the bag (10% of 10=1). Each of the grasses I talked about has a different

nitrogen requirement per year/1000 square feet. Bluegrass wants 4-6lbs per year, ryegrass 4lbs per year,

and creeping red fescue 1-2lbs per year. You never want to apply more than

one pound per application. Using our bag of 10-10-10, we get 10% of 10lbs = 1lb of

nitrogen. So we would use one full bag of 10-10-10 every application. With the proper

amount your lawn will look great all season. Take care.

Posted 2011-02-21T19:40:10+0000  by Ken_HD_CHI

Howdy, Hello, and Hi,


Coach Dave here and since I'm on the West Coast the other garden experts thought it a good idea to reply to the "What are the numbers on fertilizer" question, but also what types of grass we use here in California.


                                                            (nitrogen)        (phosphorus)        (potassium)

The easiest way to remember is :     UP,           DOWN,  and    ALL AROUND.

                                                                  15     -          15      -      15



Up: Nitrogen promotes top growth.

Down: Phosphorus promotes good roots.

All Around: Potassium benefits the whole plants health and pest resistance.


When looking at types of grass the drought tolerance, disease tolerance, wear resistance, shade tolerance, recovery from moderate wear, winter color, and heat tolerance are taken into consideration.



Tall Fescue: This is the most popular and is usually found in a seed blend form. This grass is famous for being able to adapt to most types of soils, drought tolerance, disease resistance, and self re-seeding.



Bermuda: Very popular on golf courses, sports fields, and parks. This grass is very resiliant to wear, however the hybrid versions do not produce seed, so yearly re-seeding is needed.



Annual Ryegrass: Many people use this for their lawns during the winter months.  When the spring/summer starts it dies off allowing the dormant grass you might have to come back to life.



St. Augustine: This grass is very hardy and recommended for people with dogs because of it's dense growing pattern. It is often associated as being a type of crabgrass because of it's sideways growing root system. St Augustine can withstand salt laden soil such as beach communities. Cold climates and shade make for poor growing conditions of this hardy grass.



If you take a moment to read the fertilizer guide printed on the back of the bag, this will help you with your fertilizing decisions.


 Here is lawn expert Dave Kruckenberg in a quick video giving us some great information on fertilizing.


Yours Respectfully,


Posted 2011-03-14T19:17:21+0000  by Dave_HD_OC

So with N, P, K, which would be the best to use when there is no old grass, and you are starting from the begining

Posted 2011-04-29T15:24:20+0000  by Elaine1

In Valdost G.A.. Sorry I didn't post where I am talking about

Posted 2011-04-29T15:27:43+0000  by Elaine1

 Howdy,Hello, and Hi Elaine1,

It's "Coach Dave" at your service.  It's warming up and I'm sure your ready to get your lawn in to shape so let's discuss what your options are.

Centipede and St. Augustine grass are the two most common types of grass in your area.

Centipede grass spreads by production of above ground horizontal stems called stolons. 

centipede 2.jpg

or if you have St. Augustine which produces rhizomes.(underground stems)



Here is what you can use for your established lawn.

  ScottsBonusS.jpg    StVigoro.jpg    Hyponex.jpg

Bonus S has 29-1-10 has weed killer added with the fertilizer.

Vigoro Ultra Turf has 28-3-3 is mainly for St. Augustine, but will be fine for Centipede grass.

Hyponex has 15-15-15 and is a general purpose fertilizer, and a great choice as well.


These have different NPK ratings, but they are all formulated for your area.


Happy Gardening,


Posted 2011-05-02T19:30:50+0000  by Dave_HD_OC


Popular Grasses for the West Coast


The West Coast has some unique weather, which allows certain grasses to stay green year round.  Some popular grasses for the West Coast are Fescue, Bermuda, Rye grass and St. Augustine. 


With the typically dry climate present here, keeping the lawn properly watered is very important.  Our swings from hot to cold are not too extreme most of the year, but our winter temperatures can vary greatly from the coastal areas to our mountain locations.





Many homeowners like to plant Fescue because it will stay green all year long, providing it is watered regularly.  A Fescue lawn can be attained with either seed or sod.  Our mild winters allow this grass to stay green throughout out colder months, which is why it has been a popular grass with West Coast homeowners.





A strong and durable grass, Bermuda has also been very popular and can be found throughout all of the Western areas from the coast to the mountains.  Although a durable grass, Bermuda does not like the cooler weather we have come Fall and Winter.  When our nighttime temperatures dip into the 30’s and 40’s, and our ground temperature falls below 45°-50° F, Bermuda grass will go dormant for this period.


Rye grass



In Southern California, Rye Grass, annual or perennial, is a cool weather grass.  In some areas, Rye Grass can be used for those cooler shady areas but mostly Rye Grass is used during the winter season and usually goes dormant in the Spring when the ground temperature rises above 50°. 


St. Augustine



Popular in the South and in much of Florida as well as on the West Coast, St. Augustine grass will give the homeowner a thick and durable lawn Spring, Summer and Fall.  Depending on your location out here in the West, your St. Augustine may take a siesta or be partially dormant during our cooler weather during the Fall and Winter seasons.



In my yard, my back yard lawn will go almost completely dormant while the front yard will stay mostly green during the winter.  You can thank Micro Climates for that disparity.


Many West Coast residents will over seed with the winter Rye Grass during this period to keep a green lawn. Some residents have had success using a heavier nitrogen fertilizer in the Fall, before ground temperatures fall into the dormant zone for St. Augustine.


A great advantage of having a St. Augustine lawn when you have children and/or pets like dogs, St. Augustine Grass will better tolerate animal urine.  Rather than just dying, this grass will self-repair.  With a little help, using  1-2 tablespoons of dish soap and a 1-2 gallon watering can, you can help to bio-degrade the urine into some usable nitrogen.



St Augustine grass is a coarse textured grass that spreads by stolon’s. It does not produce any rhizomes. The stolon’s can grow to be several feet long and root at the nodes.



Regular deep watering during the morning hours will be necessary for successful growth of your St. Augustine out here on the West Coast.  With the ability of having a deep root system, your St. Augustine will perform better with regular deep watering.  I have had St. Augustine in my 3500 sq. ft. front yard for over 30 years. I deep water for about 30-45 minutes once a week/10 days and have one of the greenest lawns on my block.



Fertilize every 2 months using a medium nitrogen fertilizer such as Vigoro Lawn Fertilizer.

Just be sure you water well before you apply your fertilizer.  Wait for the grass to be dry to the touch then apply as directed.  Water again right after application.


Avoid watering your St. Augustine lawn at night.  As the temperature cools down, it creates a great growing environment for fungus, especially here in SoCal.


Be sure to share your ideas and questions with us here at:



Posted 2017-12-29T20:04:40+0000  by Rick_HD_OC
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