Question:
Last year, I replaced the plastic sheeting in my yard with landscape fabric to prevent root rot from harming the plants. The fabric was topped with bark to suppress weeds. It worked last year, but now grass and other weeds have appeared throughout the area. Why isn’t the weed fabric doing its job working?Answer:
- The landscape fabric didn’t let you down.
- It is superior to plastic as a weed barrier around plants because it allows the soil to breathe and evaporates excess moisture.
- A two to three-inch layer of mulch smothers weeds and prevents the weed seeds from germinating. That did happen in your case, as the mulch layer wasn’t thick enough.
- Bark and other organic mulches decompose, adding aesthetic appeal to the landscape. This process is not merely decorative but a form of passive composting.
- The larger particles break down into smaller ones, while the smaller particles continue to decompose. Eventually, the soil will support the growth of desirable and undesirable plants on top of the fabric.
- We do not live in a sterile environment. The annual vegetation on the hills produces seeds dispersed by the wind. In non-irrigated areas, seeds remain dormant until the rainy season, and where there is moisture, the weeds germinate throughout the growing season.
- Landscape fabric only controls the weeds beneath the barrier; those resting on top of it will sprout over time. Thus, it is never regarded as a long-term solution.
- To correct things, I’d add more mulch to create a thick layer and smother the existing weeds. Treat the area with Round-Up oa similar non-selective herbicide for tall weeds, ensuring that desirable plants are protected from the spray.
- It is important to refresh and replace the mulch every three to four years. This means removing the old mulch from the fabric and separating it into fine and coarse collections.
- The coarse chunks are blended with the new mulch before reapplying to the area, while the fine pieces can be incorporated into other soil amendments or used in potting soil for container plants.
- Another option is applying a pre-emergent herbicide to eliminate the dormant weed seeds before germinating. The pre-emergent herbicide can be applied directly to existing plants without harming them.
- A nursery professional at your favorite garden center can assist you in choosing the best product or solution for your yard.
- Depending on the size of the area, both granular and liquid solutions are available. You treat irrigated and non-irrigated areas differently, as water activates the chemical barrier. Also, please don't cultivate the treated areas, as this will disturb the barrier. Each solution will remain effective for an extended period, so be sure to check the label for the specific timing.
Question:
When is the best time to prune Lantana?Answer:
- I’d trim and shape Lantana once the danger of frost has passed.
- It's anytime between the middle of March through early April in the Bay Area.
- Along the coast, this would be now; inland, I wait until April. After pruning, fertilize with an organic all-purpose fertilizer.