What do the numbers on the bag of fertilizer mean?

Did you ever wonder what the 3 numbers on that bag of fertilizer represent? Yes, they are there by law, but knowing what they mean may help you better decide for yourself what’s best for your turf.
Sometimes that bag labeled “Step 1″ might actually be better suited as a “Step 4″ for your particular situation. Sure, the company that markets that bag of fertilizer would like you to think they know what’s best; but then why do they sell the exact same products in stores from New Jersey to Wyoming and down to Georgia? Aren’t soil conditions different around the country? It’s time you learned to think for yourself DIY’er!

Those 3 numbers are called the fertilizer’s “analysis” and represent the percentage of nitrogen, phosphorus and potassium that is available from the bag. (Actually, it represents the percentage of N, P2O2 and K2O that is available, but for our purposes, nitrogen, phosphorus and potassium will do.) Using the fertilizer “20-10-10″ as an example, the bag with this analysis will contain 20% nitrogen, 10% phosphorus and 10% potassium.fertilizer analysis

Now, you’re probably thinking that 20 plus 10 plus 10 only adds to 40%, so what’s in the other 60% of the bag? Depending on the brand of fertilizer, the rest of the bag may contain micro-nutrients like iron to turn KY Bluegrass, Blue and other filler material (like Urea). The filler material (in which the nutrients are suspended) allows you to evenly apply the nutrients across the area you want to fertilize. If the filler material were not a part of the mix, you could potentially over-or-under-fertilize certain areas creating un-even coloring or burning. The filler material allows for a uniform application of the nutrients.
Understanding the fertilizer analysis is essential to purchasing and applying it correctly. Let’s next explore what each element does in your lawn.

  • Nitrogen – Of the 3 major elements grass plants need, Nitrogen is the staple. This is what gives grass its rich green color and makes it grow hardily and reproduce itself by thickening up. A healthy, thick lawn will naturally resist weeds and other pests and require fewer pesticides.
  • Phosphorus – does most of its work in the root system. Strong, healthy and deep roots are able to support more blades on the top, so don’t overlook this element.
  • Potassium – works right along with the nitrogen to help toughen the roots and foliage, which enhances your lawn’s ability to resist drought, wear and tear, disease and extremes in temperature.

Typically, I will NOT use fertilizers with analysis’ like 33-3-3 or 35-0-2 (we are talking about synthetic fert here). In my opinion, these rates create way too much top growth (way too much nitrogen in this fertilizer analysis) and offer little else for overall turf health, although your lawn will be very green if you use them. I like to spend the extra money and use ratings that look like this: 20-20-10 or 20-10-10. Some companies refer to these analysis’ as “starter fertilizer,” and while they are great for new seed, they are even better for existing lawns. Sometimes, what’s healthy for the baby is also healthy for adults.

The final consideration is in knowing how much fertilizer to apply to your lawn (the ‘rate’). Most products can be applied at a 1-pound per thousand rate, which means that one pound of fertilizer is applied to a 1,000 square foot area. This is pretty tough for you to figure out at home, spreaderso I recommend you experiment a little with your broadcast spreader. Put exactly 1 pound of play sand in your spreader, measure out a 1,000 square foot area, and go spread the sand. Adjust your spreader accordingly until you can completely cover that area with the single pound of sand (each pass with the spreader overlaps the previous one back to the wheel marks). If you can do it with sand, you should be ready to actually apply the fertilizer and get pretty close to the 1-pound per thousand rate.
If you find the 20-10-10 product at 1-pound rate does not give you the green-up you desire, then up your rate to 1.75 pounds per thousand on the next go-round. After that, it’s just a matter of fertilizing on an “as needed” basis. If you irrigate your turf regularly, and you live in the Midwest like me, you may put down 5 or 6 or even 7 applications per year. If you use slow-realease organic fertilizers, then 4 or 5 will be sufficient.
On a final note, you will find that analysis in natural fertilizer products is much lower. (something like 8-4-7) This means that if you want to use a natural or organic product to fertilize your lawn, you will nee to put down as much as 17 pounds per thousand like with Milorganite (my favorite organic fertilizer) to achieve the same results that the synthetic rates will at 1-pound per thousand.

Pesticides, Weeds, Your Lawn and our Environment

I hope by now, many of you are starting to think about the coming Spring and what that means for you and your little patch of green love you call a lawn.

I’ve written previously about organic, natural and synthetic fertilizers in general, and also attempted to explain a little more about their regulation and usage in residential settings. I fear, however, that most of you were bored to death and didn’t much care about the literal “poop” of the lawn care world. Just remember: those 2 posts were speaking of fertilizers and NOT weed killer and pesticides. In this post, we’re gonna touch on some of the more polarizing issues in lawn care (killing weeds and lawn insects) and how they relate to the environment. Finally, I will followup with a post of my specific recommendations on treating your lawn to obtain excellent results while keeping an eye out for the good of our eco-system.

But first, let’s learn about killing weeds and pests in the home landscape.

A pesticide, according to the Environmental Protection Agency, is “any substance or mixture of substances intended for: preventing,  destroying, repelling, or mitigating any pest.”(some of you are thinking now about your ex-wife, but, please, let’s stay on the topic of lawn pests ok? :) )
The EPA continues their definition by adding: “Though often misunderstood to refer only to insecticides, the term pesticide also applies to herbicides, fungicides, and various other substances used to control pests.”

For purposes on this post and this entire blog, we are focusing our efforts on pest control specifically in the lawn (herbicides and insecticides), which would encompass weeds (dandelions, creeping charlie, clover), unwanted grasses (crab grass) and insects (grubs).

A Personal Note 

No one, including me, will tell you that spraying pesticides is “safe.” My own grandfather owned a pest control company in Florida in the 1970s. In The Sunshine State, 70% of homes have orange or grapefruit trees in their yards, and my grandfather would contract with homeowners to protect these trees from insects such as fruit flies. I believe he also used traps in trees to ward off fruit-stealing rodents. Nonetheless, in those days, technology and research were not as prevalent, and my grandfather passed away from lung cancer … he was in his mid-40s.

Today I believe that research and the flow of information via the internet make for “Safer” products in general as companies seek to do the right thing via peer pressure and public outcry. But there are still things we just do not know, and it is for this reason we must strive to strike a balance between our need for a beautiful lawn and the environmental stability of future generations.

Who Are the Biggest Pesticide Abusers? 

Sorry to blame you, dear reader, but it’s you and/or your neighbors! Most homeowners who treat their own lawns utilize 4-step-type granular products that contain everything needed for the season, all conveniently packaged in 20lb bags. Included in at least 2 of those “steps” will be what are known as “Weed-n-feed” products, as well as some type of crab grass preventative, also termed “halts.” Some 4-step deals have also begun to include insecticides to prevent or kill grub worms. The most widely used home 4-step granular system is the Scott’s Company program that also includes Grub-X grubworm insecticide.

The Scott’s 4-step product achieves excellent results when the directions are followed. Their synthetic fertilizer is top-notch and contains micro-nutrients such as iron to give bluegrass lawns a deep-blue/green color. Their weed control is also fairly effective considering its granular nature, and their grub control is professional grade. So where’s the problem?

Here is why using a 4-step program is environmentally irresponsible

  1. It assumes that ALL lawns are created equal, and therefore all need the same thing. As a homeowner, do you think that your lawn in Arkansas has the same composition as my lawn in Chicago? (I’m mainly referring to the composition of the soil in this analogy.) While buying a “one size fits all” fertilizer program is easy and will get you results, it may not always be best for the environment, and, how much fun is that anyway?
  2. Yearly bagged programs contain an overabundance of nitrogen. Impatient customers expect a super green lawn, super fast, and synthetic, high nitrogen fertilizers bring those results, but at the cost of ruining the soil and causing accelerated top growth of grass plants.
  3. The bag that is labeled “weed-n-feed” means that you are spreading weed-killer (herbicide) over your entire lawn whether weeds are present or not. This is the worst one folks! Why would you throw weed killing products in a place where there are no weeds? But with granular, bagged products, you have no control.
  4. Similar to the above but in the case of grub worms, if you buy a bagged product that contains fertilizer and grub killer, you have to spread the insecticide over the entire lawn. However, grubs will normally not appear in shaded areas, meaning you don’t need to put the insecticide there…but with the bagged products, you have no choice.
  5. Finally, there’s the “fudge factor” in applying these products. This one mainly falls on the homeowner, but also on the manufacturer as well. When you look at the bags you buy, they will normally read something like, “covers lawns up to 5,000 square feet,” and then they will also give you some approximate settings to use depending on the spreader you have in your garage. This labeling assumes the homeowner knows the size of his lawn, and then, can calibrate his spreader to exactly cover the desired areas. In addition, most homeowners will use the “eyeball” method of spreading fertilizer and put it down as heavy as they “think” it needs to be applied. That ain’t good!

So What’s the Responsible Alternative?

You cannot completely eliminate the use of pesticides in your home lawn if you expect to get results, but you can greatly reduce their use with just a few tips, a little time and a keen eye. But I will tell you this: Don’t waste your money on beat juice or some other cockamamie organic pesticide for weeds! That may be good for the environment, but it’s terrible on your bank account!’

The best way to reduce or nearly eliminate pesticides is to utilize liquid products that you mix in a home sprayer or hand can, or purchase pre-mixed products in spray bottles. Be sure when buying pre-mixed weed killing products, you buy ones SAFE for LAWNS, meaning they will not kill grass, only weeds. These are referred to as “selective herbicides.” Next, when spraying these products, don’t blanket your entire lawn (unless the problem is outta control, then see below). Take some time and hit each individual weed according to the instructions on the bottle (this is where the keen eye comes in…stay organized and methodical). This means that pesticides are going only where you specifically target them to go, reducing the overall usage significantly.

If your lawn is riddled with weeds due to lack of previous care, then you can mix your own herbicide in a home-sprayer and blanket the worst areas with a fine mist (follow label instructions). Chances are that only one treatment in this fashion will eliminate 70% of the problem (especially if we’re talking about dandelions) and the remainder can be managed on an individual basis. This is still utilizing less product than a granular alternative and still gives the applicator (that’s you) the ability to control the amounts being put into the lawn.

Each Year, Less Pesticide is Used! 

The good news here is that once you have one year (maybe 2) of solid control under your belt, you probably will need almost no weed control ever again! Dandelions, for example, drop new seeds in later Spring, but if you eliminate them prior to the seed head popping (the cottom ball-looking thing) you won’t have a bad problem the next year. In my lawn, I never see more than 4 or 5 weeds (of any kind) per year because of the care I took in the beginning. Those 4 or 5 weeds are pulled up as I pass by with the lawn mower, meaning I use NO persticides at all!

Another concern of homeowners is crab grass or similar grassy weedsthat ruin a lawn’s appearance. I do recommend using a pre-emergent herbicide in the sunny areas of the lawn in late Spring for at least a couple of seasons. However, you need to realize that crab grass will only germinate in thin turf areas! Thicker lawns keep it choked down to a minimum. Once again, I do not need any of these herbicides in my thick, carpet turf.

As far as insects go, grubs are the big one in the midwest. Most people are unaware, but a lawn can withstand a fairly heavy grub worm attack and show almost not damage (assuming you mow your lawn tall and keep it properly irrigated and fertilized). Grass plants are very resilient and fill in and around struggling spots very quickly. I’d recommend only treating for grubs if you find them, and only then, treat specified, sunny areas.

With the above in mind, you will see that healthy turf really only requires your chosen fertilizer product and water … and almost no pesticides.

The key to reducing pesticides in your lawn is THICK TURF. Thick, lush grass will resist or hide most problems on its own, and isn’t that we ultimately want anyway? In the next installment, I will give you the secret to a super thick, healthy lawn that is dark green and uses almost no pesticide products. It will take some work to get there, but I know you can do it, for the good of our environment!


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