Weed fabric is a somewhat divisive subject among many gardeners and landscape designers. Some are sworn by it, while some outright hate it. Both groups of people have some valid reasons to love and hate weed fabric as a weed control measure. With so many opinions on both sides, most of them stem from genuine experiences rather than a hunch. So, let us take a look at the issue and attempt to break it down objectively.
A Brief Overview of Weed Fabric
Before we break down the various pros and cons, let us have a quick overview of what we are discussing about here so that we are on the same page. Weed fabric, sometimes known as weedbarrier or landscape fabric, is a woven or spun bonded fabric made from usually synthetic materials such as polyester or nylon. Sometimes simple flexible black plastic sheets are also used for the purpose, but are strongly not recommended. This fabric is laid on the ground, and a layer of mulch is laid over it. Its primary purpose is to prevent the growth of unwanted weeds in the area that is covered by the fabric. The mulch over the fabric is usually not conducive to plant growth, and hence any weed seeds landing in it will most likely not grow. Also, it prevents the growth of any weeds under it by obstructing the path for the stem to sprout out of the soil and restricting light.
Advantages of Weed Fabric
Many landscapers prefer laying a weed fabric as an essential part of setting up a yard or landscaping in the garden. When used properly, weed fabric does perform its primary function pretty well – weed control. A long time ago the quality of weed fabrics available used to be pretty terrible, and use of flexible plastic sheets as weed fabric causes various issues. But today, thanks to modern materials used in fabrics, there are various different great quality weed fabrics available that are quite durable as well as resistant to UV rays, in case the mulch covering is too thin. Once you lay down the weed fabric, the weeds will not be completely defeated, but your work with respect to regular de-weeding will be significantly reduced. This is much better way of weed control than regularly using potentially harmful herbicides.
Once laid out, a good quality weed fabric can last for up to 10 years. It is quite versatile and by cutting and laying the sheets aside each other, you can get an appropriate ground cover for your entire yard. There are many different kinds of weed fabric available in the market with varying degrees of heft and permeability in order to suit the soil and the environment. The more permeable fabrics allow more air and water to circulate through it, while a heftier and less permeable fabric will be more effective at weed control and be more durable. You can be assured that you will be able to find something to suit the soil and climate at your place. Weed fabric can be used for weed control in planting bays, patios, walkways and decks. Weed fabric is also sometimes used in the construction of these structures for evenly distributing the stress and prevent the local sinking of structures such as walkways and driveways.
Disadvantages of Weed Fabric
There are plenty of people who dislike the notion of using a weed fabric since the effectiveness of the weed fabric is limited. One important limiting factor is how well it has been used. It is necessary that there are sufficient overlaps between different sheets, the edges are done properly and the sheet is firmly held in place using ample of pins. The improper application will significantly decrease the effectiveness of the weed control properties. Also, it is not exactly a permanent solution. Good quality fabrics deteriorate over about a decade, and cheaper ones much earlier than that. After that, replacing the whole thing is a major work. Many people argue that you are trading reduction of modest regular de-weeding work for a major overhaul after an interval of few years. Also, the necessity of mulch on top is still present with the fabric. If you use an organic mulch like shredded wood chips, it will naturally degrade after a few years, mix with some dust and form a new layer of soil. New weed seeds can take root and grow on this layer of soil, hence negating the weed control properties of the fabric. Also, when the weeds do grow, either because some tough ones penetrate the fabric or because of new soil layer on top, they are much harder to uproot since their roots entangle with the weed fabric. This makes a regular de-weeding operation much more complicated.
Many also argue that a weed fabric degrades the quality of the soil. Some fear the leaching of chemicals from the plastic materials into the soil. Also, heftier and less permeable fabrics cause a significant reduction in the aeration and water percolation into the soil, leading to the death of many micro-organisms necessary for a healthy soil. It also causes an exodus of insects such as earthworms, which are essential for maintaining a healthy and loose soil. A weed fabric also keeps the organic mulch away from the soil, and hence the decomposed organic matter does not naturally mix with the soil layer below. Soil which is devoid of micro-organisms, insects and organic matter is absolutely detrimental to plant growth. It is devoid of nutrients. And usually gets quite compacted and impermeable for root growth. Add to it the fact that some roots may still grow through it and get entangled with the fabric, and cause problems when you need to change it. Hence, you may damage the plants you want to have when you remove the fabric after it has degraded. Hence, it is no wonder that some passionate gardeners absolutely hate it and prefer other methods for weed control instead.
Finally, it is clear that weed control fabric has some merits when used appropriately, and it has come a long way from what it used to be. But while implementing it, one must have realistic expectations as to how effective it will be as a weed control measure. It is also wise to take into consideration the demerits and problems that may arise due to the use of weed fabric.