Rock mulch is often used in perennial flower beds because it absorbs the sun retaining heat, which for some flowers is an important element of growth. Dark stones absorb more heat than white ones. Larger rocks are easier to remove from gardens that pebbles and crushed rock mulch. It helps prevents soil erosion and can be used for garden pathways.
Rock mulch is often made of gravel with stone the size of a pea to much larger. It is often mined from river beds and comes in large variety of colors and sizes. It works well with gardens with slopes and hills.
Pumice or lava rock is a lightweight mulch that comes from volcanic eruptions. It retains moisture very well. It takes longer for water to be absorbed into the soil so if you water for a 1/2 hour you will have to set the sprinkler to one hour. Once it penetrates and mixes with the soil this water is absorbed much quicker.
Wood chips and shredded bark are another popular mulch for gardens. Shredded bark and wood chips provide moisture retention for the garden. When it rains, the mulch will suck up extra moisture. When it gets hot, the water is released so the plants have plenty of moisture in the heat.
The wood mulches are good when used on the top of the soil. Don’t dig them into the ground. They cover and protect plant roots well in both hot and cold weather. Some of the popular wood mulches that people use are oak, red cedar, hemlock, pine bark, and white cedar. Many bark mulches are shredded which makes it easier for the mulch to decompose. Cedar mulch repels insects and is especially great in a garden where termites are present.
When purchasing stones, wood bark, or wood chip mulch, talk with a local mulch expert to find the best kind for your type of garden. This will save you time and the frustration of buying the wrong kind of mulch that won’t work well in your garden.