In truth this is an absolutely not possible. After fighting weeds on hundreds of acres over decades of weeks, I can assure you it is just not possible. Nothing is sure in life but weeds and taxes. It is best to Accept the fact that one will have to deal with them after a while.

That plastic will begin to deteriorate and poke up through the mulch looking very unsightly. Don’t try to remove it after a few years either, it will fall all apart and be partly under the dirt and partly stuck in the root systems of the maturing shrubs. You’ll not be able to till up parts of the bed for a new look without angst over the canabis light being all bound up with strips of plastic and rocks wedged tightly between the tines.

Landscape plastic will only delay the weeds and cause another series of problems. It is commonly known that plastic repels water. That little hole left in the plastic sheeting around the base of your shrub or tree is not going to allow enough water to pass through to the roots at all. The fuller the leaf canopy, the less water will drip down through to the center instead the majority of the moisture will run off around the drip line. Plastic does not breathe either and healthy roots need air along with their water for plants to be healthy and flourish.

Stone mulch will either make the roots hotter or colder, depending on the weather as stone radiates heat and cold. The reason for mulch to be applied is to insulate the root system from extremes and help retain moisture longer to promote the health of the plants. Those plants that need air to the roots will not thrive under plastic and stone where insufficient air makes them weak and sickly.

While stone may look good to some — it is very costly and dirt will still collect on the top of the weed barrier. As soon as things start going to seed around the protected area, there will be weeds everywhere in the stone rooting into that thin layer of deposited soil on top of the plastic. It is inevitable that weed roots beneath that plastic will creep around under it searching for an escape from the dark. These undercover and unwanted roots will never be found to eradicate, making them a constant problem to try and get rid of.

Landscape cloth is better in that it allows consistent moisture and some airflow to roots, but it does let weeds pop through the small holes in the weave. Once you have a weed rooted through the fabric, you will never be able to pull the roots. These contrived barriers in the long run will only make the installation more costly and a false belief that you will now be weed-free. Landscape cloth has beneficial applications in some situations and is best left to control erosion and not weeds.

If you simply must have mulch, the best choice for your shrub and tree beds is shredded hardwood or cedar bark mulch. Shredded bark mulches are fuzzy along the edges causing them to mat down and knit together after a good rain to stop erosion of loose soil to a great extent. Wood mulch encourages bugs to take up residence in it as deteriorating wood is their natural habitat. This will add the cost and need to spray chemicals on the mulch to control bugs that would never have moved in plain soil. Many is the horticultural professional who will not apply mulch to their planting beds for several reasons beginning with the insects it attracts. Secondly, they are aware that over time wood mulch decomposes to be soil again, thereby raising the soil level around the plants in the bed (causing future health problems with plants such as trees). Thirdly, because it makes it more difficult to weed the bed.