Bare soil is a good gardener’s enemy. Although some old-school gardeners still believe in clean, tilled rows of exposed soil, most of us know better. Covering the soil serves a number of purposes, and in my opinion, the top one is that it suppresses weeds. Gardeners hate weeds because they stunt the root growth of your own plants, and compete with them for natural resources.
Besides that, mulch also protects all soil types in several ways: retaining moisture by slowing down evaporation, and helping maintain a steadier temperature, all of which promote plant growth.
If you think of the soil horizons (the various layers which compose the soil), you want to protect the topsoil, usually a couple of inches of organic soil that make the ideal environment for plants and animals to live. Further down is the subsoil, home to the root zone of your plants, enriched by mineral particles and organic matter that leeches from the topsoil. By covering the land surface you protect the fertile soil from erosion and keep all the nutrients your plants need
There are many options when it comes to covering your soil: organic mulch, stone mulch, even rubber mulch. So which one should you use?
What Is Stone Mulch?
Stone mulch is the name given to small rocks that have shown to be a great ground cover for gardening. There are three main varieties: gravel or crushed stone, pumice stone, and rock mulch. They differ in size and properties, but they all are widely used by landscaping professionals to keep crops in good trim and prevent erosion. Depending on how much you need, you can buy a number of cubic yards or just get a few bags.
Advantages of Stone
If someone or something is dependable they are “like a rock”, aren’t they? Stone mulch is as permanent as it comes - it will not disintegrate, it will not discolor, and it is quite unlikely to wash away or fly around with the wind.
If you want to “set it and forget it”, to quote Ron Popeil, then stone mulch is definitely the best option for protecting your front yard or garden beds from erosion.
Less Expensive in the Long Run
We’re all watching our wallets nowadays, and stone mulch seems like a bigger investment up front. However, if you keep in mind that landscape architects usually replace wood mulch twice a year, you can easily see how there is a false economy in paying less for mulch because you will have to keep paying it over and over and over.
If covering everything in stone mulch is too big a stretch for your budget, consider doing it in parts. After a few months, your entire garden will be beautifully covered in stone mulch, and you will not have to pay for mulch ever again.
Many gardeners like to think of sod as a sort of groundcover, keeping the areas under trees, shrubs, and bushes free of weeds much in the way mulch does. However, lawns are notoriously thirsty, and it is more eco-friendly to go for drought-resistant options such as rocks. They will still be nice to walk on, and won’t require lots of watering and mowing.
Stone mulch also has an environmental advantage over chipped wood or bark mulch, since no trees have to be cut to make it.
It’s hard to imagine something that needs less maintenance than rocks! No watering, no mowing, no replacing twice a year, all you have to do is shovel them in place and enjoy your garden for years.
If you use stone for your front yard landscaping, you can be sure of constant curb appeal for a long time with minimal effort. Since the rocks make it harder for weed seeds to reach the soil, there is less weeding on your part.
What is the Best Stone for Landscaping?
Let’s get into some details now! Stone mulch and decorative landscape rocks have a lot going for them, and there are many options to suit all the uses you can dream of.
First and foremost, these are not meant for mulching - you need little stones or crushed rocks for that. But large stones can be perfect for edging the areas where you want to use rock mulch, and they can also be used to discourage people and pets from walking in certain areas of your garden - this is known by landscaping pros as “Traffic control”. Larger rocks are ideal for places where you need good drainage, since water will trickle easily around them, and they will keep your landscaping fabric in place with their weight and heft.
Some drawbacks are that large stones are not as easy to shovel or spread around, so installation will be more difficult and may cost more. They also limit your options for plants, since it takes tall plants with sturdy stems or trunks to look good next to big rocks. Finally, they’re not as easy to hose down if you need to clean them, although they do not require very frequent cleaning.
If you want to use stones as mulch, or for home improvement projects such as a new driveway or pathway cover, small rocks are your best option. For starters, they’re super easy to install, spread and clean. If you are using them for walkways, they compact very nicely after a short time, for an easy and comfortable walking experience, and pets can navigate them much better - dog paws, in particular, appreciate small rocks as opposed to larger ones.
Small stones and crushed rocks are much easier to plant in since smaller plants can thrive among them without looking crowded.
The old adage says that rolling stones gather no moss. Neither do small stones. However, they are also more likely to be dislodged by running water or careless feet, so make sure to dig them in or create a barrier to keep them in place.
Lava rocks are born in volcanoes, and they solidify when lava comes out from underground and cools in the Earth’s surface.
Since lava rocks are porous, they are much lighter than traditional stone, and this makes them ideal as mulch since they have the advantage of being able to retain water. Pumice stone is a favorite stone mulch for many landscape experts, for its water retention properties and its attractive dark gray color.
Usually black or reddish, larger lava rocks are very dramatic, good for dressing a garden bed or creating a focal point. Lava rock lasts forever, so you can consider it an investment in landscape design that you will enjoy for years to come.
Word to the wise: lava rocks are full of sharp edges, so think carefully about where you place it because it will be difficult to move. Also, don’t even think of planting something on it or around it that requires weeding or maintenance, unless you’re prepared for getting scratched regularly. Also, you shouldn’t get a lawn mower anywhere near lava rocks.
Dramatic lava rocks require their space - admire them from a distance!
There are many more types of rocks you can use to embellish your garden - read about them in our blog on how to choose decorative stone.
Advantages of Mulch
Organic Mulch will Keep Soil More Moist
Organic mulch material, such as chipped wood or nut shells, contains water and also absorbs it easily. If your plants are very thirsty and must be kept very evenly moist, mulch may be a better option, since it is constantly releasing moisture into the soil.
Sandy soils are well known for draining well, but if your plants prefer to have more moisture available, and you cannot afford to amend your soil at the moment, mulch may help retain more moisture to help your plants thrive.
Less Expensive Up Front
If you can’t afford to get stone mulch, organic mulch is a cheaper option. However, keep in mind that even though it is a smaller expense, it is one you will have to make more than once. Consider perhaps replacing organic mulch with stone in sections, or saving up and making the larger investment for the long run.
What is the Best Mulch for Landscaping?
If you’re going the organic route, let’s talk about what’s readily available to cover your garden beds in a more traditional way.
Also called brown mulch, this is the most popular mulch, and you can buy it in convenient bags in every local store and most garden centers. Since it is the default groundcover preferred by gardeners, there are many options, both in terms of how coarsely or finely it is chipped, and in terms of looks for every landscape design. Shredded wood comes in colors ranging from dramatic black to warm browns and lighter yellows. Match it to your plants, your fence, your house - the design possibilities are exciting!
There are also special kinds of shredded hardwood, also known as engineered wood fiber, which are the only ones approved for commercial playground use. This is because a playground surface must fulfill certain conditions in terms of child safety, fire resistance and stability. Make sure that the wood comes from a certified source because wooden pallets (a common source of wood chippings) are treated with chemicals which may be harmful to your plants.
Good compost is a gardener’s best friend - besides doing all the jobs that mulch does, compost also conditions the soil, giving your plants added nutrients and boosting their growth and productivity. Buy it in your local store or make your own, and remember to lay on just as much as you need for the job - if you want to promote plant growth, 1-2 inches are enough; but if you want to make sure no weeds see the light of day go for at least 3 inches (this is not recommended if you have shallow plant roots).
One drawback: it tends to wash away more easily with heavy rains, so make sure you contain it well and reapply as needed to keep your soil protected.
What About Rubber Mulch?
A controversial new addition to the mulch market, rubber mulch is made from recycled tires, which makes it arguably the most environmentally friendly option. It has some distinct advantages from organic mulch - for example, you only need 1 ½ inches of it to keep weeds from sprouting, as opposed to 3 inches with other ground cover materials. Also, it is naturally insect resistant and it also deters ants, since they cannot build nests or feed from it.
The jury is out on it in terms of looks - although rubber mulch comes in colors that mimic nature (and also crazy colors if that’s your thing!) many detractors complain that it does not look natural.
Also, there are chemical and biological considerations: there is still no clear research on whether rubber mulch leaches chemicals into the soil, although that is a claim that can also be made of some wood chippings made from treated pallets.
Is Rock Better Than Mulch?
This is a decision you will have to make on your own! Consider carefully your priorities: Price? Convenience? Looks? Delicate plants? Whatever your garden’s needs are, there is a mulch out there that is just right for you, and we hope you find it.
Whether you choose rock or mulch, we deliver nationwide.
Minick Materials has been supplying landscaping materials since 1958, and we carry a variety of stone mulch, as well as compost, wood chip of many varieties, and nut husks. Contact us and we will be happy to advise you, whether you are looking for a small amount or seeking to buy in bulk. While prices, promotions, styles and availability may vary, we always carry top quality products at great prices. And remember, we ship nationwide!