Question:
Several years ago, I replaced the plastic sheeting in my yard with landscape fabric. The fabric was to stop the root rot that was killing the plants. The fabric was covered with bark to control the weeds. It did the job for but last year, and now there is grass and other weeds throughout the area. Why isn’t the weed fabric working?Answer:
- The landscape fabric didn’t fail you. The situation changed.
- The fabric is superior to plastic as a weed barrier around plants as it allows the soil to breathe letting the excess moisture evaporate. It also prevents weed seeds from germinating and with a thick layer of mulch it suffocates other weeds.
- However, it’s not a permeant solution.
- Bark and other organic mulches decompose while adding an aesthetic look to the landscape. It’s not thought of in this fashion, but it’s a form of passive composting.
- The more prominent particles become smaller, while the smaller particles become tiny and so on. You end up with soil that supports the growth of desirable and undesirable plants on top of the fabric. Now add in another factor.
- We don’t live in a sterile environment. The annual vegetation on the hills produce seeds that are redistributed by the wind. In non-irrigated areas, the seed lay dormant until the rainy season and where there is moisture the weeds germinate though out the growing season.
- Landscape fabric will only control the weeds under the barrier. Those resting on top of the fabric sprout in time. Hence again, it should never be thought of as a permeant solution.
- There are several options in dealing with this problem. Every three to four years, you rotate and replenish the mulch.
- This would require you to remove the old mulch from the fabric and separate it into fine and coarse piles. The coarse material is mixed with the new mulch and spread back over the area.
- The fine material is then added with other soil amendments or potting soil for container plants. Another solution is to leave the mulch in place.
- You then spray the weeds with Round-Up or similar non-selective herbicide and be sure to protect the desirable plants from the spray.
- Once they have died off, apply a pre-emergent herbicide to kill the dormant weed seeds before they germinate. The pre-emergent herbicide can be applied right over the top of existing plants without harming them.
- The nursery professional at your favorite garden center can help you decide which product or solution is best for your yard. Depending on the size, there are granular and liquid solutions. Also, you handle irrigated and non-irrigated areas differently, because water activates the chemical barrier.
- Also, you do not want to cultivate the treated areas, as you will disturb the barrier. Each solution will work for an extended period, so, check the label for the specific time.
- With a new or revamped landscape, the landscape fabric or plastic is unnecessary if you adopt the pre-emergent strategy.