Lots of the more-experienced forum members often mention that a preferred treatment for a problem involves the use of products that you won't find at your local HD, Lowe's or Walmart. Hell, you won't even find most of them at a good garden center. If you want to use them, you're going to find yourself at either a Lesco (or equivalent), or it's off to a little shopping on the Internet.

Before you dive in and just order and get better (and sometimes cheaper) products from the part of the gardening world that is aimed at the professional, you should read this posting and know what you can expect. To be frank, you're going to get your eyes opened.

You see, the instructions don't get written for the homeowner. Period. They won't coddle you. There won't be pretty pictures showing you how to do it. The instructions are written for people that do this stuff for a living, and may be making a batch of a product 20 gallons or more at a time. It will be taken for granted that you know what tank-mixing, surfactants, agitation and adjuvants are. And if a product strongly advises a surfactant or adjuvant, either get it or at least ask on the Forums whether it is really optional, or really a required supplemental purchase.

Don't buy it and then come on here and rant that the manufacturer isn't doing their job. 99.9% of that product that gets purchased is going to be to be to people that can't remember the last time they saw a hose-end sprayer. You are the weird stray 0.1%.

Be prepared to do a fair amount of basic algebra and conversion work. Often the label will specify the application rate in pounds per acre. Got 5,000 sq ft of lawn? Do the math.

Also, be aware that most of the products don't have "safety fudge factors" built in. While many big-box store products will tolerate a mistake of as much as 2X the product being applied, professional products have no such safety margin. Overapply and you'll be very, very sorry.

You'll get help on BL with your math, but don't show up and say "I don't understand the specification sheet, please do the math for me". Every person that has the experience to do the math quickly went through learning it too. And they KNOW that if you don't at least try the math yourself, you'll be back next time just as clueless. At least prove that you tried the math, and we'll point out your mistakes (nicely, too!). That way you learn how to do it. The people that help you weren't born with the knowledge of how to do it - they learned it the hard way.

I've received PM's from people that feel that if (for example, not real) Gary and JG discuss some professional product and other people read the posting, then Gary and JG are obligated to do all of the math for them. Wrong! You take personal responsibility for everything you do, whether you read it here or not. You buy it, you figure it out unless someone has the time and graciousness to help you.

Professional products that are available to the homeowner/enthusiast are a boon that has only happened in the past ten years because the Internet makes them much easier to find. Use them, but know what you're getting into first, and use them responsibly.

I think the punchline for the professional products is to not over-apply. Sounds obvious to the average Joe but getting 2 gallons spread over 1000 sq ft is not as easy as it seems either the first time you try it.

Some of this stuff is so strong that the turf guys won't put in on a residential lawn. No joke. The risk/reward is not there as then they have to pay to repair the damage.

For what its worth I found it easiest to convert everything to a psf calculation in excel and work backwards.

For those who don't remember, 43,560 sq. ft./acre. Measuring out a 20x50 area and seeing how much product your sprayer puts down in that area is important for figuring out the rate of your particular sprayer per 1,000 sq. ft.

Also, I find that I overlap a bit more with a spreader tracker as I try to get it very even; in that case I had to lower the rate by about 20% on my next fill-up.

Totally agreed. As one of the mathy sorts, I'm capable of doing the math with the numbers you give me, but expect that I'm going to walk you through it.

Complicated? Yes. You'll get an answer and I'll show you how to do it. And if one of your assumptions or measurements is wrong, we have a problem. Potentially a big problem.

Consider--Certainty, one of the staples around here, has a really fine line between killing P. annua and killing your beloved bluegrass. Guardrail, over-applied, will discolor the lawn and damage it (at best).

And those two are hardly unique, nor are they the most powerful things available for some applications. Some of those I refuse to use on the lawn for that reason--the fine line is too fine for me to risk it. You'll never see me playing with Round Up to slow growth, for example, although it can be done.

This is not organic methodology where amounts don't matter. You can't wing it.

I've received PM's from people that feel that if (for example, not real) Gary and JG discuss some professional product and other people read the posting, then Gary and JG are obligated to do all of the math for them.

Exactly. I'm pleased to help, but I've ducked out of a few threads because I just wasn't sure--and not sure isn't good enough. You'll never hear me say something like "somewhere between 20 and 60 pounds per thousand, anything is fine" because it isn't. That would be corn, which is not known to do damage. Many of these are 0.75 ounces active ingredient per acre (for example), and the line between works-doesn't work-kills other things is terribly fine.

You must be precise. You need to know what you're putting down as far as active ingredient goes, and you better know that before you start. I know, with my four gallon sprayer and my standard step, exactly where I'll end up when the tank is empty (I'm always within a single footstep of that point). You need to know that as well, and realize that dilutions often matter.

You'll get help on BL with your math, but don't show up and say "I don't understand the specification sheet, please do the math for me".

Plus if you don't have a feel for what you're doing, a mistake becomes that much more likely. I could tell you bloody stories.

Professional still scare me to use on my yard and I used to mix and spray the greens for a golf course in college a few years ago.

An old guy had taken home some "Revolver" which is a post emergent and pretty strong IMO. We told him to use .5 ounce for a 4gallon Stihl Sprayer. He did not listen and used something like 4-5 ounces. Needless to say, he almost killed his grass.

ALMOST?

Being organic usually makes this simpler. In fact the complications with measuring chemicals is one of the big reasons I decided to go all organic. With organics it is hard to make a mistake that will hurt anything but your wallet. Secondly, the app rates are not that complicated. For the liquids, the app rate is usually a gallon per acre. Reaching for my trusty Google.com, I find that if I type in "1 gallon per acre in ounces per 1,000 square feet" the result pops up as = 2.93847567 US fluid ounces per (1000 (square feet)). I round that off to 3 ounces. Actually I round it further to 2-4 ounces. With ground grain fertilizers, the application rate of 10-20 pounds per 1,000 square feet is a good starting place. After that it is either a matter of how much you apply or how often.