Mulch improves soil, stifles weeds

  • Wed Mar 24th, 2010 11:36am
  • Life

By Cindy McNatt The Orange County Register

Think of mulch as a cozy blanket for your soil. The key word here is blanket, and thicker is better. If you were going to tuck your soil in for the summer (or the winter, for that matter) you could blanket it with all kinds of things.

Some commercial farmers use plastic. Landscapers mulch with weed cloth followed by bark or gravel. Vegetable gardeners sometimes use a layer of newspaper followed by a layer of mowed grass, hay or straw.

Of course, the most organic form of mulch you could choose is a mix of ground up and decomposed forest products or your own homemade compost. Mother Nature mulches her soil with deep layers of fallen leaves.

Mulch isn’t something you sprinkle lightly on the top of your soil. Like a blanket, it’s all about thickness. The idea is to smother weed seeds under a deep, dark cover so they can’t germinate. The ideal thickness would be 2 to 3 inches of mulch laid on top of your native soil.

Mulch has benefits besides preventing weeds. It can also smother soil-borne funguses such as black spot, mildew and rust and prevent those spores from traveling up from your soil and onto your susceptible plants such as roses.

More, mulch also keeps soil temperatures even, prevents evaporation so you water less, and adds all-important organic matter to improve your soil structure and provide a feast for the earthworms.

Ultimately you want a mess of earthworms in your garden. And those earthworms would pull your mulch down into the soil to improve it. But earthworms don’t live where there is little organic matter, so don’t expect them right away.

I mulch once a year at most. Because I am an active gardener, at some point during my digging, weeding, planting and fussing, I’ve dug my top layer of mulch under into the soil, making it fluffier and more organic all the while.

Come spring, I usually order another large batch and re-apply the mulch 2 to 3 inches thick everywhere I find bare soil.

But there is no need to dig your mulch under at all. You can simply lay it on top and let nature take it course. You might find, though, that your mulch will still need topping off every once in a while.

It is important to keep mulch 2 to 3 inches away from the crown of your plants — the area where the stem meets the soil. Too much mulch at the crown can cause crown rot by trapping moisture.

But do mulch any area that is open and unplanted and especially under the canopy of your plants — the green leafy areas.

Mulch the entire landscape for a tidy appearance. Mulch the roses to keep the soil evenly moist and smother fungus. Mulch the vegetable garden to keep weeds under control.

There are many ways to get mulch. In larger landscape areas you can let leaves fall where they may; just don’t rake them up.

You can make your own mulch in the form of compost with shredded leaves, bark, yard waste, grass clippings and vegetable scraps from the kitchen.

You can also purchase mulch. Bags are fine for small properties, patios and potted gardens. If you have a large landscape, you will find it most cost effective to buy mulch by the truckload.

Most topsoil yards will allow you to pick up your mulch. Approximately one yard fits in the back of a pickup truck.

If you need 2, 3, 10 or 20 yards of mulch, you might want to have it delivered. The delivery truck will dump a mountain of mulch in the street in front of your house. Warning: The mound will be highly attractive to house cats and bored neighborhood children.

Mulch is not the same as topsoil, nor is it the same as a chemical pre-emergent product. Mulch is made of lightweight, decomposed or composted green materials, while topsoil is dirt with mulch mixed in, and chemicals are chemicals.

Use a wheelbarrow to transport mulch and start spreading.

To find mulch, do an Internet search with the keyword “topsoil” and your region and you will turn up lots of local companies that provide mulch.