On 6/8/2010 9:08 AM, MICHELLE H. wrote:

I am hoping that someone can explain this to me. Is there something up
with "Home Depot" and the "Scotts Company" with false bag weight
contents or something??

Anyway, last year, when we put down the "Scotts Turf Builder Lawn
Fertilizer with Plus 2 Weed Control", that we bought from "Home Depot",
it took 2 bags ( 14.29 pounds each according to the bag ). with the
spreader setting on 5 1/2 like the bag says, to do our entire lawn.


Well this year, we bought a 5,000 square foot bag of "Scotts LawnPro
SUPER Turf Builder Lawn Fertilizer with Plus 2 Weed Control", and this
bag was 17.24 pounds ( according to the bag ), and we had enough to do
the entire lawn with the 1 bag!!

There are many potential variables that can affect the spreading rate
of fertilizer. The company manufactures a product that they've
designed to cover a specific area, but due to factors beyond their
control, actual coverage can and usually will vary.

Factors affecting coverage include: the physical formulation of the
product; the condition of the lawn (flat/hilly, bumpy/smooth,
soggy/dry); the individual's stride/walking speed; the amount of
overlap between passes; whether the spreader is properly calibrated;
the condition of the spreader (if it's allowed to get rusty, the gate
lever may not correctly open or close); for drop spreaders, the length
and dampness of the grass can also affect dispersal (damp grass
wetting the bottom of the spreader can cause granules to bunch up at
the opening); whether the specific fertilizer has an actual spreader
setting for your specific brand/model of spreader on the bag.
(Contrary to common belief, there is no universal standard for
spreader settings. One model's '5' may be another model's '3.5' or
'7'.) So if your model isn't on the bag, you've gotta guess.

Thus, there's no sure way to tell how your particular spreader is
going to apply a product until you try it yourself. It is prudent to
use a lower setting the first time and see how it works, and note the
results. I've learned with the spreader and products _I_ usually use,
and my length of stride, that a setting that opens the gate about 1/3
usually works out for the best for _me_. But, just as with cars, YMMV.

So my question is, why is it that with the drop spreader setting both
set at 5 and 1/2 both this year and last year, and doing the exact same
areas, why is it that last year we used 2 bags that were 14.29 pounds
each, of the "Regular" Turf Builder to do our lawn, but this year, it
only took 1 bag of the "Super" Turf Builder, which was 17.24 pounds.

Could it be because the the "Super" Turf Builder is 29-2-3, and the
"Regular" Turf Builder is 28-1-4. Does that have to do with how big the
granules are, and how much comes out??

The numbers refer to the percentage of the three primary nutrients
contained in the fertilizer. It is always listed as a percentage of
weight in the following order: Nitrogen (N); Phosphors (P); Potassium
(K). For established lawns, nitrogen is the major nutrient that greens
the grass and stimulates blade growth. In short, nitrogen makes the
grass grow and makes you mow. Phosphorus stimulates the production of
roots, runners, and stolons, to multiply grass plants and make a
denser turf. Potassium also works on root development as well as
winter hardiness. Nitrogen tends not to persist in the soil; it will
move downward or run off, and cheaper forms of nitrogen will oxidize
to a degree into the atmosphere if it is not watered in soon after
application. Over-application of nitrogen can also result in burning
the turf. Phosphorus and potassium are much more stable elements that
move slowly through the soil, so they usually don't need to be applied
at anywhere near the same rate as nitrogen.

Nitrogen is the element used by the industry to calculate coverage for
any particular fertilizer product. For the typical lawn, the average
rate of application is 1 pound of nitrogen per 1000 square feet,
though the rate can vary between 1/2 pound and 1 pound depending on
the manufacturer's specifications. But the rule of thumb for the
homeowner is: 1 lb/1000 square feet.

So - to determine the minimum recommended coverage of any bag of lawn
fertilizer, you just need to figure out how many pounds of nitrogen
are in the bag. It's easy. Multiply the percentage of nitrogen by the
weight of the bag. The "Super" Turf Builder analysis 29-2-3, and the
weight is 17.24 pounds. 17.24 times 29 percent is 4.9996, so there's
basically 5 pounds of nitrogen in that bag; thus, the minimum (and in
this case, recommended) coverage is 5000 square feet.

The 'Regular' Turf Builder was a 14.29 pound bag with an analysis of
28-1-4. 14.29 times 28 percent is 4, meaning there's four pounds of
nitrogen in that bag, so the minimum coverage is 4000 square feet. But
in this case, the manufacturer decided to declare the bag covered 5000
square feet, just by deciding to apply less nitrogen than the standard
guidelines. They can do that, and a comparison of the two products
means an application of regular Turf Builder supplies 25% percent less
nitrogen than the Super Turf Builder. If you wanted to go by the
standard 1 lb N/1000 square feet guideline, you could just apply the
Regular Turf Builder at a somewhat heavier rate than the
manufacturer's suggestion. Just be careful not to apply too heavily,
or you risk burning the lawn. And never forget to water it in well
within 24-36 hours after application. That not only reduces the risk
of burning, but it ensures that the maximum amount of nitrogen goes
into the soil, instead of oxidizing into the atmosphere. You paid for
all of it, so water it all in.

Because why is it that last year it took 2 bags of the "Regular" Turf
Builder 14 pound bags, which is over 28 pounds to do our entire lawn,
but this year 1 bag of the 17.24 pound "Super" Turf Builder, from the
hardware store was enough??

As noted above, but this time short and sweet: many, many variables
affect the spreading rate. You ended up over-applying last year's
product, but you properly applied this year's product. Now that you
know how to calculate bag coverage, and know that spreader settings
are a crapshoot, use a low setting next year, buy only enough to cover
the area, and pay attention while spreading. If it's dispersing too
quickly, make the spreader's gate opening smaller to slow it down.