Though, there are 3 ways you can use it to your advantage.
If you are a homeowner, you most likely prefer landscape fabric as an alternative means to suppress weeds. That’s because landscape fabric is non-toxic and it acts as a blanket that suffocates weed seedlings, which kills them before they have a chance to sprout. Landscape fabric “is constructed from woven fibers or manufactured as a solid sheet with perforated holes to allow water to soak through. Some brands offer UV protection to maintain the life of the fabric,” (Glenda Taylor and Bob Villa on bobvilla.com).
Landscape fabric is 3 feet wide and comes in rolls of anywhere between 50 and 200 feet in length. The cost also varies depending on thickness and length of the fabric – the thicker the fabric, the more able it is to suppress those pesky weeds.
On the surface it appears that landscape fabric does the job in keeping the weeds at bay and it certainly does have a couple of benefits.
1. Landscape fabric smothers weed seeds
Weed seeds need light and air to grow but landscape fabric blocks out the sun rays from filtering into the soil, thus smothering weed seeds.
2. Prevents erosion from winds and heavy rains
This is especially true for slopes. Landscape fabric on slopes protects the surface soil from washing away with running water.
As much as we’d like to view it as a miracle product, landscape fabric has more disadvantages that outweigh its benefits.
1. It doesn’t just kill off weed seeds
Weed seeds aren’t the only seeds that landscape fabric smothers. Seeds from beneficial plants, carried by birds and wind, and dropped into the soil that has now been covered by fabric, are also smothered as they, too need light and air in order to grow.
Landscape fabric also smothers earthworms and other important micro-organisms that are needed in order for our plants to thrive. Earth worms aerate the soil. They also need air in order to survive; air that they can only receive at the soil surface. Landscape fabric prevents them from doing this.
2. Prevents moisture from penetrating the soil
While landscape fabric prevents evaporation of moisture from soil, the perforated holes in the fabric aren’t large enough to allow a sufficient amount of moisture to penetrate the soil. Over time, the covered soil becomes dry and compact.
3. Landscape fabric heats up the soil
Since landscape fabric is black, it absorbs the heat from the sun’s rays. So, not only does it dry out the soil, it heats it up. This is bad for the oxygen-thriving micro-organisms that need a certain temperature range and moist conditions in order to thrive and carry nutrients to our plants that depend on them to grow.
4. It acts as a barrier to mulch and other organic matter
Mulch and other organic matter, like twigs, needles, and leaves that fall from trees, breaks down over time, adding more nutrients to the soil. Landscape fabric acts as a barrier to this natural organic matter.
5. It doesn’t kill off all weed seeds which makes it even more labor-intensive
Even the thickest of fabric won’t keep a good weed down for long. The hardiest of weed seeds will still manage to germinate and penetrate the fabric. This makes it extremely tedious, labor-intensive, and time consuming when it comes to weeding a garden bed that is covered in landscape fabric. That’s because the landscape fabric prevents you from being able to remove the weeds by their roots.
In order to effectively and permanently remove weeds from your garden bed, you will first have to remove the fabric and that will entail also removing all of the mulch or gravel you’ve decided to lay over the fabric.
Given the above-mentioned disadvantages, landscape fabric is not recommended for garden beds.
So, can you use landscape fabric at all?
The good news for all those homeowners and gardeners who love landscape fabric; there are 3 ways you can use it to your and your garden’s advantage.
If you live in a windy area, or high above a steep hill, then your garden will benefit from the use of landscape fabric because it will prevent erosion. Or, if you want a dessert garden with crushed gravel, sand, or a combination of both, then you will want to consider laying a thick landscape fabric over the soil. You should then add a 2-3-inch-thick layer of washed crushed gravel on top of the landscape fabric and then tamp it down firmly. That will ensure that very few weed seeds will survive. And when they do, it won’t take you hours of backbreaking work to remove them from your garden.
You can also use landscape fabric over a fallow garden bed just for the purpose of killing weed seeds. If you’re building a garden bed in summer or in early fall, instead of planting right away, remove all weeds from the new garden bed, cover it with a thick landscape fabric – some gardeners use carpet or black plastic – and secure it firmly with pegs so that it doesn’t blow away in the event of strong winds, and leave it until the following spring.
After the threat of frost, remove the landscape fabric and then till the soil while adding in plenty of organic matter within the top 6-12 inches. Remove any and all surviving weed seeds. Finally, plant your selected plants and then add a 2–3-inch layer of mulch on top of the soil.
Taylor, Glenda and Bob Villa. “All You Need to Know About Landscape Fabric”, bobvilla.com, 25 October 2021 https://www.bobvilla.com/articles/landscape-fabric/