Question. I really enjoy your show andwanted to know if you could suggest a brand of mulch that's naturallyblack in color. The mulch I've purchased in the past starts out black,but turns brown. Thanks,
---Kimberly inWilmington, Delaware.
Following your advice, I called a nursery about getting leaf compost touse instead of mulch. They couldn't understand why we wouldn't want touse mulch. They said compost would burn the trees because it was tooacidic. They also said if it's used in the right amount and isn'tmoist, wood mulch works perfectly and has never caused a problem. Isthis true? I would like to use compost, but I'm discouraged by what thenursery is saying.
---LisaIn Merchantville, NJ
Dear Mike: I'm seeing a lot of shredded, dyed rubber mulch made fromused car tires in home stores. My brother in Hollywood, FL, has startedusing it, but I don't even like calling it 'mulch'. I only use composton my garden beds, but my brother likes the quick fix and I'm worriedthat the rubber mulch will break down and release byproducts that couldcontaminate the shallow water tables in places like Florida.
---Steve inMorrisville, PA
I am looking for the best way to remove shotgun fungus spores from mysiding. I read the articles from Ohio State University, but didn't seeany mention of removal strategies. Thank you!
---Barbara inNorthern Michigan
Answer. Ah yes, 'tis the season ofMulching Mistakes. Tell you what—I'll answer all those questions andmany more, and sum up everything you need to know about this topic in aseries of tips and treatises we will call:
The Ten Commandments of Mulch
1. The word "mulch" does not mean wood chips orshredded bark. "Mulch" isanything that covers the soil to retain moisture and prevent weeds.Nurseries would LIKE you to think that wood = mulch because they'reoften paid to take wood chips and shredded bark from tree cutterstrying to avoid high landfill costs. If they can then sell it to you asmulch, they get paid twice.
2. There is no better mulch than compost.No, compost is not acidic and it doesn't harm plants (it's plantFOOD!). But nurseries have to actually buy compost, so some might tella little…eh, 'fib' to achieve that higher profit. Did I just say,"fib"? I'm sorry—that's not fair. I meant to say: "Liar, liar; pants on fire". Iapologize for the error. Anyway, in a groundbreaking study from Iowaand OhioState Universities two inches of compost prevented weeds just aswell as two inches of ground wood mulch. And the compost provided allthe food it's plants needed for the season, while the wood mulchactually increased the plants' need for food (see #9, below). You gonnabelieve some guy what wants to sell you wood to make a bigger profit?Or the published results of University researchers?
3. Compost is pretty. When I spoke with that study'slead researcher, Dr.Dan Herms, he observed that the compost mulch was as black and nicelooking as the dyed black wood mulch they were testing it against. Itlooked so nice, in fact, that he switched to it personally. Simply put,a mulch of compost provides all the benefits you can get from mulchwith none of the negatives of wood or other troublesome mulches. Othermulches of high regard include shredded Fall leaves, pine needles andpine straw; and really cool esoteric local ones like cocoa bean shellsand rice hulls.
4. Wood mulch is not nice—especially dyed wood mulch.It's made bygrinding up old pallets and other trash wood, and may contain arsenic,creosote and other nasty stuff. It is the lowest quality mulch you canbuy. Oh, except for…
5. Rubber mulch is WORSE! You know you have to pay tothrow away your oldtires. Do you really think it's a smart idea to buy them back aftersomebody grinds them up and calls them mulch? Rubber mulch leaches zincand other pollutants; and it STINKS in the summertime. Why doeseveryone with a toxic waste disposal problem always have to think,"Hey—I'll bet we can convince people to use this stuff in theirgarden!"?
6. Thou should not use wood mulch near thy home. Asmany hundreds oflisteners have told us they learned the hard way, any kind of woodmulch—like wood chips, so-called triple-premium shredded bark and thoseincreasingly popular root mulches—can breed a nuisance mold known as'shotgun' or 'artillery' fungus that will permanently stain homes andcars within 30 feet of the mulch with impossible to remove fungalspores that look like little tar balls. Sorry, but the reason UniversityBulletins don't offer removal tips is that once they dry, thosespores are there for good.
7. Thou should not run ANY mulch right up to thyhome. Everyone in Americahas subterranean termites in their landscape. Subterraneans prefer totravel under cover. Mulching right up to the side of your home withanything—even stone—provides the protection and moisture they requireto find their way RIGHT to your framing. Always leave at least asix-inch area clear around your home.
8. Never touch a plant with any mulch. Mulches arefor preventing weedsand retaining soil moisture—they are not blankies; they do not keepplants warm or comfort them. Just the opposite, in fact: ANY mulchthat's piled up against a plant stem or tree trunk provides cover andtraps moisture, inviting pests, disease and rot to destroy that poorplant. There is no good reason for mulch to ever touch a plant; thereare many good reasons for it not to. Always leave a few inches wideopen around the trunk or stem.
9. Wood mulches starve plants. As we have oftenwarned, wood is high incarbon. Carbon seeks out nitrogen to help it break down into soil, justlike in a compost pile. Mulch your plants with wood and the wood willsteal their food in its quest to become really nice dirt a few yearsfrom then. When I hear that a plant isn't thriving, my first responseis generally, "get rid of the wood mulch".
10. You CAN use wood mulch! It's great for smotheringunwanted plants andkeeping weeds down in walkways far away from homes and cars.
For even more info, check out last year's diatribe on this topic:
You Bet YourGarden ©2006 Mike McGrath