A gentleman from Hudson stopping in and asked me this week if he should put down landscape fabric around his fruit trees as a mulch. My answer surprised him.
For most trees, shrubs, and flower beds, my answer is usually “no.” That immediately grabs people because almost everyone has been told the opposite.
Landscape fabric is excellent for certain uses and it is poor for others.
Let us look at why many folks buy it. Many gardening advertisements promise fewer weeds, less maintenance, and longer lasting beds.
Sounds wonderful. But here is what really happens: The leaves fall. Dust blows in. Grass clippings accumulate. Pine needles collect.
Then a couple years later…You’ve created soil on top of the fabric.
Guess where weeds germinate? Right there above the fabric. Worst case is that now their roots grow through the fabric and pulling them becomes harder than if no fabric had been used.
So, they add another layer of fabric to cover that mess and in time, the same problem occurs.
Meanwhile, the organic matter that has naturally accumulated on top will break down but provides little to no advantage to the soil below.
Organic mulch keeps improving the soil as it breaks down and is incorporated into the ground. I don’t care if you use ground wood chips, pine bark, shredded leaves, or pine straw.
All of these are ‘organic’ and they conserve moisture, moderate soil temperature, feed earthworms, add organic matter, and improve soil structure as they decompose.
Landscape fabric doesn’t do those things.
The hidden problem is the roots. Many shrubs naturally have shallow feeder roots and those roots eventually grow into the fabric. Those roots may live happily under the fabric but if the fabric is working as intended, then those roots cannot reach the newly developed organic matter that lies just above it. Conversely, if the weed barrier tears or becomes compromised, you will have root intrusion and when you work on the beds, you’ll likely damage the plants they were meant to protect.
Extension agents like myself see this constantly.
Now, landscape fabric does have many excellent uses. They work great under gravel paths, decorative rock, erosion control, with French drains, and in many, short term, commercial nursery situations.
It’s the wrong product under living landscape beds.
Now when applying organic mulches, let us be sure to do that correctly. Never pile up bark in a ‘volcano’ shape up against the trunk of trees or shrubs. You may like the way it looks but it creates an environment for disease and insects to thrive that the bark of the trunk has a difficult time repelling.
Mulch should be applied no less than two inches and up to four inches deep is just fine. I have heard the application to look like a ‘donut’ or even the top of a bagel. We want that mulch to be applied liberally and in a wider circle than most folks imagine.
Nature has been mulching forests as long as there have been trees. Our gardening grandparents mimicked that and used what they had at hand. Healthy soils are built from materials that eventually become part of the soil.
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Cary Sims is the County Extension Agent for agriculture and natural resources for Angelina County. His email address is cw-sims@tamu.edu.
Educational programs of the Texas A&M AgriLife Extension Service are open to all people without regard to race, color, sex, disability, religion, age, national origin, genetic information, or veteran status. The Texas A&M University System, U.S. Department of Agriculture, and the County Commissioners Courts of Texas Cooperating.
