Rock and mulch garden


Rock vs Mulch — Which Should You Use? — Bustling Nest

When used properly, rocks can add a touch of beauty to your garden. I’m sure you’ve seen stunning gardens with rocks lining walkways or stylishly diverting the water flow on a property. But did you know rocks can also be used as mulch for your flower beds or around your trees?

Today you’ll learn the details of rock mulch and which types of stones are commonly used. We’ll also detail the best ways to use each type of stone mulch in your landscape design plans.     

This article will also compare traditional mulch and rock mulch side-by-side so you can see what each of them brings to the table, which one is better, and which is cheaper.  The good, the bad, and the ugly.

Keep reading to the end of the guide to learn steps to installing rock mulch.

Rock Mulch

Rock mulch is ornamental pebbles or stones that act as a decorative ground cover on flower beds, around tree bases, fire pits, gardens, pools, ponds, and a host of other applications.   Pea to ping-pong ball-sized gravel (sometimes much larger) are sourced from river beds or areas with rocky terrain.  The gravel is available in a wide variety of textures, colors, and dimensions. 

The multitude of textures and colors affords homeowners the ability to be very precise in their landscape design choices.  With traditional mulch, you’re usually limited to choosing from different shades of brown.  Even “red” mulch has a brownish tint to it.

Types of Rock Mulch

Decomposed Granite

Decomposed granite is the most common igneous gravel formed as hot magma or lava cools and solidifies.  It is composed of several other minerals that include mica, feldspar, and quartz.  The solidification process results in the formation of large crystals that flake and crumble over time.

Decomposed granite is what is left over after the crystals undergo natural weathering and fracture into smaller pieces. 

This landscaping gravel is available in over 30 colors.   DG, as they refer to it in professional circles, can be bought as rough stone or as a finer material that has been further crushed and screened depending on what you will use it for.

Its versatility, ease of installation and maintenance, and excellent drainage are a few reasons people choose decomposed granite.

Applications for this landscape stone depend on the form that you purchase it in. 

The forms and their applications include:

Natural Decomposed Granite

Natural DG works best in areas of your lawn or garden that grass and other plants have difficulty growing.  It will not attract pests to the area and lasts longer than most other varieties of mulch.  It has the bonus of providing the soil and surrounding plants with small amounts of nutrients.

Decomposed Granite With Resin

Combining decomposed granite with resin results in a more permeable and natural-looking form of asphalt.  Often it is used in areas instead of asphalt because it is easier to install and remove while still providing a solid surface that can withstand regular traffic.   You will find this form of DG on playgrounds, pathways, and some driveways.

Decomposed Granite With Stabilizer

You can use this stabilized form of the landscaping gravel to build small pathways or even a patio surface.  The DG with stabilizer is added and tamped down onto the soil or other rough gravel to form a solid surface that is easy to maintain.

Pea Gravel

The stones that comprise pea gravel usually come from river stones that have been rounded and smoothed by flowing water.  It has earned its name because it is about the size of a pea.  Pea gravel is naturally sourced, so don’t be surprised if you find a larger rock or two that seem out of place. 

Pea gravel is used as a decorative alternative to concrete in driveways, patios, and walkways.  Its natural colors offer a comparable option to traditional mulch with the added benefit that it won’t deteriorate on your lawn.  If you have little time to spend working outside, pea gravel is an excellent option.

Pea gravel is easy to work into a landscape design and comes in a wide selection of natural colors.  Plus, it is less expensive than other types of rock mulch.

One of the major problems with pea gravel is its ability to travel.  Unlike crushed gravel, it doesn’t lock into place.  Instead, it rolls over one another and has a propensity to wind up out of place.  So using it on a sloped landscape or an area without a defined boundary may leave you with the occasional scattered stone.

Lava Rock

As its name would show, this landscaping rock is created when a volcano erupts and spouts lava onto the surface.  Over time, the lava will cool and solidify.  The rock is then harvested and broken down into the red or stones you find in your landscape.

The reddish tint on the stone comes from the oxidation of iron present in the lava during the eruption.  Basically, it rusts.  The black stones do not differ from the red except in color.  They simply did not oxidize the iron during the volcano’s blast.

These stones look best in yards where they match the surrounding terrain.  Especially in desert landscapes. 

Compared to other types of stone mulch, it is lightweight and easier to spread through your property. 

Lava rock is a good option for homeowners who have problems maintaining the soil temperature and moisture level.  It will trap the heat of the sun during the day and release it at night.  Its ability to regulate soil temperature helps it retain moisture in extreme environments by slowing water evaporation.  Putting down a weed barrier underneath it creates an effective weed suppressant in your flower beds.

Be careful when making lava rock your choice for your home or garden.  Its color and texture can prove very dramatic and pronounced, especially if you choose to use the red lava rock. 

In the end, aesthetics come down to your personal preference.  But if you’re planning on putting your home on the market soon, then choose something more in the middle of the road with strong, natural base colors. You’ll avoid alienating any potential buyers.

Remember, the first thing people see when they walk up to the front door is the landscape surrounding it.  A healthy lawn with good landscaping decisions can add up to 20% to your home’s resale value.

Besides, if you decide you don’t like it after spreading it throughout your garden beds, it is an absolute nightmare to remove it.  So be sure to do your homework before you commit to using lava rock.

River Rock

The name of these landscaping stones tells you all you need to know about where they were sourced.  Over time flowing water has rounded, smoothed, and flattened the surface of these stones.  It shaped them into the stones that are a foundational part of many homeowners’ landscape and hardscape designs.

Don’t get river rock confused with pea gravel because they are both harvested from river beds.  Pea gravel is smaller and more consistently uniform.  You can buy a load of river rock that will have stones that range from ¾” to 5″ in the same lot.  

It is very useful when used correctly in your design choices.  Whether your goal is nothing more than a simple accent or if you’re in the middle of reimagining your home’s curb appeal, river rock lends itself to an assortment of applications.

These stones can add a sophisticated, defined look to the borders of your flower bed.  Laying it onto a path or walkway can give your property an elegant yet rustic functional addition to your backyard. 

If you have a drainage problem on your property and you need to divert the water, river rock can kill two birds with one stone.  Simply create a dry creek bed that flows into a rock garden or other water collection point.  You can craft your creek bed to bend and turn as you wish to meet your design aesthetic. 

Because river rocks are round, they do not lock together like sharper gravel .  The water freely flows down and absorbs into the soil.  Lawns with poor drainage can wind up damaging your home’s foundation as it runs off the soil.

Whether you’re creating a Zen garden to relax in or building a retaining wall to curb soil erosion, river rock is a staple in landscapes today. It can function effectively in different capacities and give your property an appealing, distinguished look at the same time.

Rock vs. Traditional Mulch: Which is Better

It is better to use rock in certain circumstances and traditional mulch in others. Rocks are better at weed-prevention than mulch and are also lower maintenance. Stones can also add to the aesthetics of a property. However, rock cover is not good for gardens that receive a lot of sun because they retain more heat than mulch.

Ultimately, it all comes down to personal preference.

Before you make your final decision about your landscape mulch, ask yourself what you’re using it for.  How much time are you going to commit to upkeep and maintenance?  Are there any issues with your lawn that you’re trying to solve with this mulch? 

These are but a few of the important questions you need to ask yourself to diagnose which type of mulch is going to work best for you.  

If you don’t want to spend a lot of time working with the landscaping mulch and money isn’t an issue, then choosing a stone mulch will give you what you’re looking for.  You won’t have to spend time outside working on the stones after their initial installation. 

If you enjoy spending time in your garden and are proud of your plants and flowers’ vibrant growth and blossoming, then using organic or other bark mulches on your property is what you will probably decide on using. 

Each of these mulches, whether stone or organic or bark, comes with its pros and cons about what it can offer to the homeowner.  Remember that there’s no rule written down in some age-old lawn care text that says you cannot use both on the same lawn.  If you’re happy with its form and function, that’s all that truly matters. 

Which is Cheaper?

In terms of initial investment, rock mulch is more expensive than organic or bark mulch by two to three-fold.  The stones’ weight will increase shipping and delivery costs.   However, stone and gravel mulches are only paid for once.  Organic mulch is a reoccurring cost that you will pay every time you need to replace it.

You will have to replace the shredded bark or other organic mulch at least once per year because it breaks down over time and adds nutrients to the soil.  Rocks do not break down and are very low maintenance.

You’re going to wind up spending money no matter the route you choose. It’s up to you to decide whether you want to spend a larger amount of money upfront or spend the same amount of money (or more) over an extended period.

Your budget could be the most significant determining factor in which of these mulches you choose.  If money is your primary consideration, then get creative.  Start composting to save money on your organic mulch. The costs you reduce by using this simple, homemade organic mulch to accentuate and fertilize your plants and shrubs will add up.

Do Rock Mulches Hurt the Soil?

Stone mulches are heavier than their organic or shredded bark mulch counterparts and can cause compacted soil in areas that have a thicker mulch layer or larger stones.   Compact soil causes issues that range from water pooling on the surface to causing roots to suffer because they cannot readily access the nutrients, air, or water essential to survival. 

Besides compact soil, you could also consider the fact that rocks do not nourish the soil with nutrients like pine bark mulches and other wood chips do as they decompose.  Rock mulches will absorb the heat from the sun and raise the temperature of the soil.  This will dry out the soil and create drought-like conditions for the plants’ root systems.  If you do not have drought-tolerant varieties growing in your gardens, the plants will undergo stress that can compromise their health and growth rate.

Over time, stones can create an alkaline pH level in your soil.  Trees grow best in acidic soil conditions.  If you’re using rock mulch around your tree bases, you might compromise their health unbeknownst to you.

Pros and Cons of Using Rock

Pros
Cons

Pros and Cons of Using Traditional, Organic, or Bark Mulch

Pros
Cons

Both types of mulch offer homeowners an effective method for controlling weeds in their lawns.  They both offer different levels of soil runoff and erosion protection.  Both can transform your landscape and make it more appealing and unique.

When the time comes to decide, write out what problems you need the mulch to solve, your budget, and your design preferences.  Maybe one stands out more than the other in certain areas.  Maybe you see a need for both types of mulch in different locations in your yard.

That’s the beauty of lawn care. You’re only limited by your imagination and the knowledge you choose to gain. 

7 Steps to Landscape With Rocks

Step 1: Determine How Much You Need

To calculate how much you need, multiply the length and width of the area you plan on placing the rocks to determine the square footage. Next, divide the square footage by 80.  This number represents the total tonnage of rocks needed to cover that area in 3″ of mulch (which is the appropriate depth you will need). 

For example:

  1. You measure 16′ in length and 10′ in width
  2. Multiply 10′ x 16′ and get 160 square feet of area to cover
  3. Divide 160 by 80 and get 2
  4. You will need 2 tons of rock to cover the entire area in 3″ of mulch

Step 2: Order the Material

Call your local landscape supplier and order the appropriate amount of your chosen rock type.   Have it delivered to your home whenever it fits into your schedule to coincide with the installation.

Step 3: Prepare the Area

Remove all weeds from the area by pulling them out with your hands.  Use a garden trowel for tougher weeds. It’s important to remove the weeds from the roots to the shoots.  The entire plant needs to be taken out of the ground.

Step 4: Lay Down Your Barrier

Roll a layer of landscape barrier fabric from one end of the area to the other, going 4″ beyond the edges on each end.  Cut the fabric at the 4″ mark.

Then roll back across the area, overlapping each subsequent section of fabric 4″ onto the preceding section.  This ensures that you will completely cover the ground to inhibit weeds from penetrating through to the surface.

Repeat this task until you have the entire area covered in your barrier fabric.

Step 5: Lay Down

Begin shoveling rocks onto the edge furthest away from any buildings or walls. Work across the area towards the buildings or walls until the entire area has been covered by 3″ of landscaping stones.

Step 6: Smooth Out the Surface

Using a wide-toothed metal rake, smooth out the landscaped surface until it is uniform and level throughout the desired area.

Step 7: Water

Yes, you read that right.  Use a garden sprayer to rinse any dirt and dust that may have collected on the rocks resting on the surface.  This will ensure that it cools the soil from the heat of the day and it presents the rocks in the mulch in the best possible light by exposing the widest array of colors.

If you want to learn more about laying down organic mulch, make sure to check our starter guide on mulching.

Landscaping Pros and Cons of Rocks Vs. Mulch

After you plant new trees, shrubs and flowers, you want to add the finishing touch–mulch. Mulch makes your landscape look pristine and polished.

But, does it matter what kind of mulch you use? Or, should you perhaps replace mulch with stones?

Read on to learn the pros and cons of mulching with an organic mulch or an inorganic mulch like rocks.

Rocks Vs. Mulch–Which Is Better In Flower Beds And Around Trees?

Pros And Cons Of Organic Mulch

Pros
Cons

Pros And Cons Of Rocks In The Garden

Pros
Cons

Verdict: Organic mulch is overall better than stone. But the stone is better than no mulch at all!

Ready To mulch? Learn How To Mulch Your Landscape Here!

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Stone mulch: all about its origin and application

Stone mulch is different from other types of mulch in many ways. Where is the best place to apply it? How to lay down? What should be the care of stone mulch? Let's talk about all the features of bulk coating.

Mulch can be organic or inorganic. Each type has its positive aspects.

The most commonly used organic mulches are grass, tree bark, sawdust, leaves, needles, peat, compost, cardboard.

Inorganic mulch is pebbles, gravel, crushed stone, film.

Why stone mulch is needed

Mulch is not a new trend in gardening. In Europe, it was already used in the 17th century, when plantings were covered with straw from buckwheat. The use of mulch simplifies dacha work and improves crop growth conditions:

As for stone mulch, it is believed that it came to us from China, where it was also called stone steam. The inhabitants of this country in ancient times noticed that the stones have a positive effect on the growth of plants. They slowly heat up during the day, preventing the soil from overheating, and at night they gradually give off their heat to the earth. As a result, there is no sharp change in temperature, which favorably affects the development of plants. In addition, with a sharp change in night and day temperatures, condensation forms on the surface of stones - then moisture enters the soil and is absorbed by plant roots, which is especially important in a dry climate.

However, stone mulch not only helps plants, protects the soil from evaporation of moisture and the appearance of weeds, like other types, but also performs a decorative function. It, unlike organic mulch, is used not in the garden, but in gardens and flower beds, stones decorate lawns and the territory at the entrance to the house, they are used to decorate a Japanese garden, etc.

Mulch stones are selected based on needs. For example, in a sunny area, it is better to take a stone of light shades, because. from the dark ones, the soil will heat up more and this can lead to overheating of the root system of plants. Gravel or crushed stone up to 5 cm in size is suitable for neighborhood with shrubs, conifers or in a rose garden. Pebbles are usually poured in rockeries or used to create dry streams. Limestone contains alkali in its composition, so its use can change the pH of the soil. If your pH is above 7 then use this stone with great care.

Advantages of stone mulch

Stone mulch has many advantages:

Disadvantages of stone mulch

One of the biggest disadvantages of stone mulch is its cost. However, unlike cheap bark or free grass, this material can last a very long time.

Another disadvantage of stone mulch is some difficulty in maintenance. With a stone, it will not be possible to live according to the principle "Pour it in and forget it." In order for it to retain its attractive appearance for a long time, it needs to be regularly looked after. We will talk about caring for stone mulch below.

How to lay stone mulch correctly

Before laying stone mulch, pay attention to the advice of those who have used this type of mulching material on their site:

Stone Mulch Steps

  1. Clear the area where the stone mulch will be placed of debris and weeds. If possible, remove all weed roots from the ground so that you do not have problems with weeding in the future. Level the ground.
  2. Lay a layer of geotextile with a density of at least 120 g/m2 on the prepared soil. Geotextile performs several functions. Firstly, it prevents soil and stone from mixing. Secondly, it does not allow weeds to germinate: the denser the geotextile, the better it copes with this task. Thirdly, due to its water permeability, it allows water to pass through and acts as a drainage (for this reason, it is impossible to use a film as a separating layer in any case).
  3. Create a demarcation border to separate the rock mulch area from the remaining area. A wide strip laid from larger stones can become a border; sometimes a metal profile is used as a border. Often summer residents install a ready-made plastic curb tape, deepening it into the ground. You can also divide the plots using paving slabs, paving curbs, bricks, etc.
  4. Place a layer of stones 5-10 cm high and level it with a rake.
  5. In planting areas, move stones, make a cross cut in the geotextile, move the edges of the fabric and plant flowers, bushes or trees. After that, return the stone backfill to its place.

If you want to lay stone mulch on an area where there is already vegetation, then change the procedure: lay a layer of geotextile between the plants, and then pour stones on top of it.

How to care for stone mulch

Once the mulch is in place, only regular care will keep it looking attractive for a long time.

Mulching the soil with stones is not an easy process and not the cheapest. However, properly laid stone mulch, which is constantly looked after, will delight you with its attractive appearance for many years.

Bark mulching or rock filling? Pros and cons! |

Topsoil adds beauty and health to your garden. Mulching with rock or organic fill keeps the ground warm and moist. Prevents the growth of weeds.

Old school gardeners prefer open ground as a way to grow their garden naturally. Keeping up with the times, site owners know about the benefits of mulch firsthand. The main advantage of the coating remains the suppression of weeds that interfere with the growth of the roots of the planted plants. Competing with them for natural resources.


There are 2 main types of mulch. organic and artificial. We recommend reading about it in a separate article on our website.

5-10 cm backfill creates an extra layer on top of the soil. Maintains a favorable microclimate for beneficial microorganisms. Feeding and development of the root system. By covering the surface of the earth, you protect fertile soil from erosion, retaining the nutrients that plants need.

Decorative stone filling

Covering the soil with stone is used in landscaping and maintenance work. There are 7 basic materials for decorating the site:

Pre-prepared filling helps to zone - visually highlight certain areas. Reduce labor costs for maintaining the beauty and health of the garden.

For example, marble is used in rose gardens, fountains, alpine slides. White and colored chips are ideal for garden paths. Large stones are suitable for a dry stream, a small pond. The ways of using decorative stone in design are limited only by the imagination of a specialist.

What is stone mulch?

Filling with small stones is actively used in horticulture and horticulture. The most popular varieties are crushed stone, pumice (other substrates), gravel. Mulch differs in appearance and compound characteristics. The main advantages of stones are beauty and durability. However, they do not enrich the nutrient medium of the soil. Let's talk about the benefits in more detail.

Consistent and unpretentious

Stone mulch is reliable. Does not require regular maintenance. It is not subject to decay, decay. Not consumed by slugs and rodents for food. The stone does not need to be watered, dug up or mowed. Dumping practically does not lose color, is not afraid of moisture, frost and drying. The desire to “put it and forget it” is the main motivation for gardeners using this material for mulching.

Cost savings on course

From the point of view of investing in the beauty and health of the garden, backfilling with decorative stone saves money for the future. It provides reliable protection of plants from weeds, soil from freezing or drying out without the need to change the material.

For example, tree bark enriches the soil and nourishes the root system through natural decomposition. Despite the benefits of organics in horticulture and a noticeable difference in the cost of the material, the stones pay off faster at a distance. Mulch should be changed or refilled twice a year. Stones are laid once and almost forever.

Sustainability

The material is ideal for zoning the site. Design of paths, dumping around trees, lawns. Environmentally friendly mulch is ideal for lawns. The stone does not take moisture and does not require additional care. It is pleasant to walk on it without fear of spoiling the soil cover.

Beauty

Rare landscape design without stones. To decorate the local area, use:

Due to their enviable strength and unpretentiousness, the stones are suitable for paving paths and driveways. Visual division of the territory into sections. Large boulders form rockeries and flower beds. Backfilling with decorative stone around flower beds and trees looks expensive and spectacular. Zoning allows the use of several breeds for the play of color, the selection of even and curly lines.

The main disadvantage of the stone remains the relatively high cost, along with the available larch or pine bark, free leaves and grass clippings. The material does not supply the soil with nutrients. It is easier for weeds to germinate through large stones.

Bark mulching

Organic cover keeps moisture in the soil. Helps retain heat without the risk of drying out. During the natural decomposition process, the mulch provides the root system of plants with additional elements. Microorganisms useful for fertilizing and loosening the soil use organic matter as food. Let's talk about the benefits of bark for mulching in more detail.

Less start-up costs

Along with rocks and inorganic mulch, organic allows you to start spring gardening faster and cheaper. The bark, depending on the fraction and volume, is distinguished by an affordable price. Does not require additional backfilling for 6-12 months.

By retaining moisture in the ground, the frequency of watering and the amount of water used are reduced. Based on the advantages of "live" mulching, small costs will pay off with the enviable beauty and health of your site.

Soil microclimate

The bark protects the earth from overheating in summer, early spring and late autumn frosts. Maintains optimal temperature, retains moisture and prevents evaporation. Controls soil acidity. Due to the activation of microorganisms and earthworms, the soil is loosened and saturated with oxygen.

Weed control

Mulch prevents the growth of weeds that compete with plants for nutrients and root space. Caring for a garden is easier when the soil is covered with a layer of bark. Annual weeds will never grow through it. Years will have to work hard.

One of the main advantages of organic mulch is also a disadvantage. The bark is subject to decomposition, eaten by insects and microorganisms.

In the process of decay, it gives the soil elements useful for the development of plants.


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