Okay, troops. At ease. Let’s talk MULCH. Mulch is important. It is not only aesthetically pleasing, it serves some purposes. Aesthetically, it neatens the appearance of your landscape. It makes your AO (Area of Operation) look more squared away. Mulch really makes your landscape look like you care about the appearance of your quarters or facility. The more functional roles of mulch are: suppressing weeds, retaining moisture, insulating the soil and diminishing soil erosion. As mulch decomposes, it helps soil structure and fertility.
There many types of mulch. Opinions on mulch are just as plentiful. How your landscape “looks” is totally up to you. For example, I’m not a big fan of dyed mulch. Why? Because, eventually, the color goes away. The colorants are NOT harmful. But the colors will fade. The type of mulch you need to use does have some considerations. Does your choice of mulch remove nutrients? Does it change the pH of the soil? Could it be harmful to pets?
First off, I’ll give you my “high speed” recommendation. For my customers in the US Mid – Atlantic Region, I always recommend shredded cedar. I think this is the best. Shredded mulch “locks” together better when the mulch begins to settle. But it still allows good water penetration. Shredded mulch stays in place and decomposes faster than chips. And, the scent of cedar is very pleasing to humans but not very pleasing to pests. Those are my big reasons. The color is usually a tan or light brown which works well with many landscapes.
Just like any other mulches, there are some drawbacks to cedar mulch. The first drawback is, although it takes a long time to decompose, as it decomposes it removes nitrogen from the soil. Okay; so monitor that. You may have to fertilize your plants. This is a good opportunity for some organic fertilizer application. Secondly, cedar can get real dry in the summer. That can possibly, maybe, pose a fire hazard in some areas. If those conditions exist, wetting your cedar mulch may be in order.
Shredded cypress is my second favorite. Some folks are saying that the increased use of cypress mulch has resulted in the increased harvesting of cypress trees in the south Atlantic and gulf coast states of the US. That doesn’t sound like a good thing. But cypress mulch is pretty awesome. It does not remove nitrogen and has all the benefits of cedar mulch. However, folks that care about the wetlands in Louisiana and Florida are really concerned about the unsustainable logging of cypress down there. Some of these experts are saying all the “old growth” cypress is now gone and what’s left are newer trees and the new trees do not have the same desirable benefits as a mulch as the old trees did. So, I’d say, stay away from the cypress, if you can. The cypress forests in our south protect our wetlands and our wildlife.
Some folks in my area use fallen leaves. That’s okay. Shredding them would be better. But, remember, some leaves will alter the pH level of the soil. In most cases it will make the soil more acidic. But its an easy way to use those leaves in the fall.
In fact, that’s when you should put down your mulch – the fall. Its after the growing season. Clean out your beds. Remove all the dead annuals and perennials. Do your pruning. (Be sure to WEED!) Then mulch. It is also a good time to square away your edging.
In another blog post, I discuss using grass clippings as mulch. That’s just as lazy (but acceptable) as using leaves. But, do not use grass clippings from a lawn that has been chemically treated. Definitely don’t put that in your vegetable garden! The chemicals (herbicides, pesticides) may harm desirable plants. You’ve seen me type this a million times – Leave the grass clippings on your lawn! Grass clippings are 90% water by weight. When they are left on the lawn they dehydrate quickly. They are also high in protein and are rapidly decomposed by bacteria and fungi. Grass clippings contain about 4% nitrogen, 2% potassium and 0.5% phosphorous. Other studies have shown that grass clippings can equal up to 3 applications of fertilizer – WITH NO ADDITONAL COST OR WORK! Make sure the clippings are chewed up fairly small – get a mulching mower or a mulching attachment to your mower. It is environmentally responsible!
Wood chips are sometimes free from tree companies or local units of government. Sometimes you have to go get them. Sometimes they will dump a big pile in your driveway. They take up nitrogen and are acidic. Just better hope the trees did not have any poison ivy. And, walnut tree chips have some chemicals that inhibit the growth of many plants.
Straw is sometimes used. I’m not a big fan. Straw can easily blow or wash away. Straw can also have a good deal of weed seeds. It breaks down slower than leaves or grass clippings. You will see straw used as mulch in newly seeded turf areas. That’s normal.
Pine needles are very popular in the south. They also increase acidity but they stay put rather well. Hey, if you got conifers, pine needles look…well, natural around those trees.
Bark nuggets are not my favorite either. They do not stay in place. They wash away easily. And, worst of all, they can become direct fire projectiles if picked up by your mower. But, perhaps in some areas where there isn’t a slope, you don’t mow and heavy rain is not a factor, these could be a choice. Pine bark is the most common.
Cocoa hull mulch is popular. Its got great color, texture and aroma. But this easily blows away. It decomposes slowly. Cocoa hulls are poisonous to dogs and cats and can grow mold on the surface.
Gravel or rock is okay. Guess it depends on what kind of “look” you are going for in your landscape. They do not breakdown, do not need to be replaced, but, they do not help the soil. Better make sure this is what you want. Removing this stuff is awful.
Don’t use rubber. That’s usually from old tires. That has lots of zinc and other stuff that can wreak havoc on your soil. Newspapers are too weird and landscape plastic or fabrics look terrible. Plastic and fabrics are also real difficult to remove when the time comes.
Please, no “mulch volcanoes”. Improper mulching kills trees and shrubs! I’m serious. A mulch volcano is when inexperienced troops pile mulch around the base or stem of a tree or shrub. Placing mulch high around the base of a tree often leads to softening of the bark, disease, fungus, and pest infestation. Proper mulching should be more like an “artillery impact crater” – with the tree in the middle. Okay, okay – so you may not have ever seen an artillery impact crater. How about a doughnut? Ever seen a doughnut? You want water to be able to run down the tree trunk and into the ground, not away from the tree. And, you want water around the mulched area to possibly drain inward as well. Two to four inches of mulch should about do it. Here’s a nice document from the State of Maine:
In one home I had, I did something I later regretted. I decided to put paving stones around my beds. I “elevated” some of my beds. Then I put down a weed blocking fabric and then I covered that fabric with some red lava rocks. (Yes; red lava rocks. It was a phase I was going through.) It looked good for about a season. Maybe not even that long. Everything began to unravel, literally. Removing and disposing of all that stuff was really painful. And, it eventually made my quarters look like Mosul in 2004.
I say, stick to the natural wood mulches. It will make your life easier and make your beds very pleasing to the eye. Unless you have the time, money and resources for a mini Versailles, and André Le Nôtre is your gardener, keep it simple.