- Black Plastic
- Landscape Fabric
- Stone/Gravel
Synthetic and Inorganic mulches do a goo job of holding moisture and blocking weeds. They don’t add any fertility to the soil, but on the other hand, they don’t decompose and require replacing as often as organic mulches.
Uses for Synthetic and Inorganic Mulches
- Plastic and Landscape Fabric are good choices for around foundation plantings and other shrubs and trees. These plants don’t require frequent fertilization and, for the most part, you won’t be working in these beds regularly and so you don’t want to have to worry about weeding them throughout the summer.
However plastic gets very hot in the summer and besides smothering weed seeds, it can also kill all the good things in the soil, including plant roots, unless there is sufficient moisture. Be sure to cut holes in the fabric to allow sufficient water to pass through. If you are seeing puddles accumulate on top of the plastic or fabric, you don’t have enough drainage. Landscape fabric is porous and shouldn’t be a problem unless it gets blocked.
If you like the functionality of plastic or landscape fabric, but not the look, you can always add a thin layer of bark mulch on top of the plastic or fabric for camouflage. However, as the bark decomposes, weed seeds will be able to take hold on top of the plastic or fabric. You will also need to replace the bark as it disintegrates.
Tip: If you’re building raised beds, consider making them the width of your plastic or fabric so that you can cover the bed without seams.
- Gravel and Stone work well as mulches in areas that require good drainage and/or beds with plants that like a little additional heat, like Mediterranean herb gardens and rain gardens. Stone is hard to remove, so give it a lot of thought before using stone or gravel as a mulch.
