I'm happy to learn that many of you had the good sense to print a copy of last week's tip and show it to your uneducated, idiotic, unscrupulous or shady landscaper — the one who continues to use black-dyed mulch. If you missed it, the article was all about how that stuff is the absolute worst choice among all mulches.

Unfortunately, I understand some of you got a little push-back from landscapers who don't want to change their ways and still think there's money to be made in dyed mulches.

It's interesting to note, though, that none of the emails, Facebook posts and calls I got on the subject in the past week came from a landscaper arguing any of my points. Some are definitely going to be mad at me again this week, though, because I suspect a few are going to be fired.

At least one landscaper's push-back was that the mulch dye is "organic," made from soybean oil. Who cares what it's dyed with - it's dyed! What do they think happens to all that dye as it eventually leaches into the soil through rain or irrigation? At best, an "organic" dye is innocuous — at worst it's poisoning the soil. Either way, it's not doing anything positive for the soil or enhancing root-system growth as native mulches do with their highly shredded, composted material.

Other landscapers attempted to dispute the facts by claiming their product comes from a reputable source that makes lots of timber products. Timber Products! Remember, last week's message was all about how mulch shouldn't look like just chunks of wood, much less chunks of wood that are dyed! It's the chunks of wood that cause the first level of "nitrogen immobilization."

Here's what John Ferguson, a soil scientist with Nature's Way Resources, has to say about nitrogen immobilization: "To get the dyes to stick to the wood, producers use raw wood from pallets, crates and other trash wood. This type of wood has a carbon-to-nitrogen ratio of over 500:1!"

A good compost pile has a radio of 30:1.

Ferguson explains that when any mulch is placed on the soil, microbes start to break it down. But they need lots of nitrogen to do that. When nitrogen-deficient black-dyed mulch is used, the microbes have to get the extra nitrogen they need from the soil, pulling it away from plant roots. (Microbes always eat first). If the plants become short on nitrogen, they are far more susceptible to insect and disease issues.

Finally, some landscapers just flat-out lied about the costs, claiming that native mulches are five times more expensive. Not so! To find the wholesale price of any mulch, just call some soil yards. It's easy to find out how much you're being gouged by unscrupulous and shady landscapers.

The most expensive Texas native mulch I know of wholesales for $32 a cubic yard. The most popular is roughly $20 a cubic yard at wholesale. The average wholesale cost of black-dyed mulch is roughly $15. So, even if native mulch is double the cost, don't you think that's worth the investment?

Finally, I want to share one more thought I meant to include last week ... why black-dyed mulch looks so unnatural. It's the opinion of horticulturists and soil scientists that black does not occur in nature, except under anaerobic (without oxygen) conditions where the soil is sickly and full of bad microbes. Ferguson notes, "The most common black colorant is carbon black, which is a byproduct of the chemical industry and a known carcinogen." That's the property of black-dyed mulch that leaves your hands stained, like in the picture.

So, if you're unlucky enough to have some black-dyed mulch in your landscape, grab a handful and rub it together in your hands. If your hands are stained (LEFT), you have the absolute worst of the worst mulches available - the carbon black-dyed mulch. If it leaves no stain but you don't see dirt either, you have dyed mulch that is nothing but wood chunks, and likely colored with a soybean oil.

Finally, if you have to ask what to do now, the answer is YES! You need to get rid of it ... have it removed. And if your landscaper or yard guy is unwilling, then I guess they're fired!

Ah! Here's a great marketing idea for some up-and-coming young landscaper: In your pitches and flyers, say "I only use native mulches, as recommended by Randy Lemmon on the GardenLine."