Small stones serve a variety of functions in the garden -- besides tempting kids to throw them or drive them off in their toy trucks. Small stones work well as mulch or to define pathways and island areas. While large stones make dramatic impact, small stones can cover large garden areas with texture and color, while helping plants stand out. The garden areas you will use them to cover, will help determine the types of stone you want to use.
Small rocks and gravel make excellent mulch materials, and they work well as a bed for a garden path. The stones also help define areas when used as edging, or they can be used to cover entire spaces, such as the ground around a fountain where the stones keep the area from getting muddy.
Picking the Right Stones
River rocks are smooth and easy on bare feet, but on a path, they slip and slide underneath feet. Crushed gravel is a more stable choice. Pea gravel also works on paths; the stones are so small that they form a nice barrier between your feet and the ground. Stone mulch of any type, including river rocks, gravel or black or red lava rocks -- lava rock is so lightweight it moves around easily, so don't place near a lawn. Rock doesn't degrade like bark chips or other types of organic mulch. Stone mulch creates a permanent weed barrier -- especially when installed over landscape fabric. You don't have to stick to just one kind of stone in the garden either. For example, fill a path with pea gravel, and edge it with river rocks to help hold the pea gravel in place and create an added layer of texture.
A word of caution -- do not allow children under the age of 3 to play unsupervised in an area with small stones, which do present a choking hazard to toddlers because of their propensity to explore the environment with all their senses, including taste.
As a mulch, stones reflect and retain heat, which can sometimes damage your plants in the heat of summer. Light-colored stones reflect sunlight and heat up toward the bottoms of your plants, which can cause them to dry out faster. Dark stones retain heat, keeping the soil temperature higher than some other types of mulch, which may or may not be a benefit in winter. When you're using the stones as a purely decorative element, such as along a path or when edging a water feature, choose the color based on your preferences and landscaping design. Color choices include brown, red, black, white and tan.
Calculating How Much to Buy
As a more permanent garden feature than other organic mulches, stones often are a bit more expensive. Calculating the right amount to buy can keep you from spending too much or needing to run back to the store later when you don't have enough. Measure the length and width of the space you want to cover, and multiply those two numbers together. For a 10-foot-by-10-foot space, you have 100 square feet. Multiply that number by how deep you plan to lay the stone to find the cubic feet. For a 2-inch depth of 100 square feet, you'd have 200 cubic feet. If you're buying small stones sold by the cubic yard rather than cubic feet, divide the cubic feet by 27 to find the cubic yards.