Choosing a decorative mulch or rocks adds beauty to the landscape. Mulching of your flower beds, for purely scientific reasons, is to control weeds, retain soil moisture and maintain soil temperature in the beds during winter.
We will discuss the primary points for making the best decision for your home. The first thing would be your budget. The initial expense of using Rocks will be much greater than wood mulch or Pine Bark and Pine Straw. Rock typically cost 4 times the price of other mulch products. While the long term cost of the other mulch products will require reapplying to maintain coverage and appearance. There are many mulching options available: Shredded Wood Mulch, Colored or Natural, Pine Bark chips (Mini Nuggets, Nuggets, Large Nuggets) Pine Straw and rocks for ground cover (pebbles, stones, rocks). To plan your project, you will need to know the square foot of the area you want to cover. Using a Mulch Calculator you can estimate how much you will need. (Length and Width of the beds in feet and the depth in inches, recommended 3" of depth total) The mulch Calculator will give you the quantity required in Cubic Yards or 2 Cubic Foot Bags.
If you are going to choose Rocks you should use a weed block cloth to prevent the rocks from sinking into the soil. This will also help with week control. The weed cloth is optional when using mulch as it typically does a better job of blocking out the sun than the rocks.
Rocks do not add any nutrients to the soil where wood mulch does. Extremely high winds or areas that receive large amounts of water run-off will need to be address with rock, stepping stones or other drainage methods to prevent erosion. Rocks will need very little replenishing as they do not fade or decompose. They can be used to give a Striking impression amongst your landscape.
Wood and pine bark mulches decompose and become part of the soil and aid in water retention, weed prevention and soil erosion. Wood Mulches will need to be replenished regularly. All colored mulches fade over time. How much time depends on the amount of Sun exposure, Rain and Foot Traffic (dogs, people, Landscapers or home owners with their tools).
In the end don't be afraid to use both in your landscape design.
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