Mulch is highly beneficial in all types of gardens. It lends an assist with weed control, captures rain water to keep soil moist, and provides some much needed winter insulation to plants that would otherwise die in freezing temperatures.
The problem arises when high winds blow mulch away or a heavy downpour washes the mulch down the garden, onto pathways, driveways, or into your neighbors yard. The solution is to learn the techniques gardeners and landscapers use to learn how to keep mulch in place on all types of terrain.
The solution for your yard could be as simple as installing edging around garden beds, or it may call for the more labor intensive process of excavating soil on slopes, building terraces, or creating swales or bio-swales and planting suitable plants on the berms.
Discover the various solutions you can use to keep mulch in place in your garden.
Choose the Right Type of Mulch Suitable for the Location
There are multiple types of mulch materials, yet not all are practical for all-weather conditions. Some are better suited to open areas exposed to high winds, others compact better making them practical in wetter areas where mulches frequently get washed away by rainfall.
Organic mulches are better suited to wet areas. This include things like straw mulch, pine bark, leaf litter, cypress mulch, and wood chips. All organic mulches will decompose over time, requiring replenishing, however, they’re more prone to compacting when wet, rather than washing away. The more compacted organic mulches are, the more likely they are to stay in place.
When laying the mulch, it can help to wet it, then lightly tamp it down either by stepping on it, or pressing it down with a trowel or similar gardening tool.
Inorganic mulch materials include rocks, pebbles, decorative aggregates, crushed stone and gravel. These are better suited to open areas exposed to high winds as they are less likely to blow away given the heavier weight.
The downside to using inorganic materials such as crushed stone and similar hardcore is that they provide no additional nutrition to the soil. If you want the benefits of organic mulch and not have it blow away, you need to get creative.
Regardless of the Type of Mulch Used, It Must Be Applied Correctly
When laying mulch, it is not as straightforward as dumping on top soil and calling it a day. It needs to laid appropriately to maximize the chance of it staying in place.
When laying mulch, apply it to a sufficient depth. For fine mulches, add 1” to 2”. For courser mulch materials, apply 2” to 4”. The heavier the mulch and the more layered, and tamped down in place it is, the more likely it is to stay put.
The mulch also needs to be level. What to avoid is to any piles of mulch because the elevation can create water channels. When that happens, there’s a higher likelihood of the mulch washing away.
Smart Ways to Secure Organic Mulches
Edging for Flower Beds and Lawns
To keep mulch off of pathways and lawns, the best way to prevent mulch spreading is to edge the area. Around the perimeter of flower beds, solid edging can be installed.
This can concrete pavers, bricks, setts, or it can be as simple as installing treated timber gravel boards on straight edges, or if you need to contour the edging, use a hard plastic edging. Plastic lawn edging tends to be in heights of 3” to 6” and are thick enough to withstand years of whacking with a trim line.
On raised garden beds, a few inches space can be left between the top of the raised bed and the topsoil to allow room for mulch to be applied. Leave a couple of inches of space between the top of the garden bed and the top layer of mulch to prevent it blowing away.
Windbreaks are effective in open areas exposed to high winds. There are two ways you can use these. The first is to install solid windbreaks such as fencing, arborvitae hedging rows, or similar fast-growing trees for privacy and shelter from wind. Windbreaks can be installed some distance away from flower beds to slow the velocity of wind down in gardens.
The second option is suited to vegetable gardens and it involves growing taller vining or climbing plants that can be trained to climb a trellis. The leaves on a trellis shelters the mulch and plants from high winds.
Use a Mulch Tackifier
Tackifiers are adhesives. They are more commonly used with hydroseeding, which is when seeds, mulch, and any fertilizers or soil amendments are added to the ground surface, then a tackifier applied to bind everything together and hold it in place. There are commercial blends of mulching materials that have tackifier already applied.
A popular mix is straw with tack. These shouldn’t be used in flower beds near lawns as you’d be constantly removing grass clippings that get stuck to it. If the clippings have gone to seed, before long, you’d be needing to get rid of grass in flower beds.
How to Keep Mulch in Place on Slopes
Mulch netting is what to use to keep mulch in place on a slope, or any elevated area that’s prone to the mulch being washed away or carried away by the wind. It can be staked into the ground, but for a more secure fix, landscape staples are better suited.
Asides from netting, there are also erosion control blankets. These are usually made of aspen fiber, coconut fiber, jute, straw, or simply polypropylene (plastic) sheets.
As with mulch netting, erosion control blankets are pinned in place and are suitable for use on slopes of any gradient, regardless how steep the slope is. The most suitable type of blanket is determined by the gradient of the slope.
For steep slopes, a continuous fiber blanket completely covers the soil surface. Open weave blankets such as jute netting can be layered onto a mesh fabric and is better suited to slight gradients.
Berms and Swales Help Control Water Run-Off and Keep Mulch in Place
Berms are similar to raised beds. They’re essentially man-made ridges. Rather than planting on sloping terrain, parts of the ground can excavated to create small flat surfaces. They can be wide enough for a walkway, or just narrow enough to plant small edging plants for aesthetic appeal.
For sloping terrain, the purpose of berms and swales is to slow down the flow of rainwater and capture most of the water in the swale.
As the water is captured, it infiltrates into the soil where its movement is slowed.
Swales are typically wider than they are deep. They are not the same as a trench. Trenches divert water. Swales capture water, slowing its movement, but it still seeps into the soil. These are installed at higher level elevations to allow the water to slowly move downhill.
To make the most of a swale on sloping terrain, pathways can be formed. Similar to erecting terraces to create flat surfaces for planting on and securing the mulch on with netting, you can use wood chips or similarly dense mulch materials to form a path.
The mulch will decompose over time, so the pathway will periodically need topping up. The denser the layers of mulch, the better the compaction will be.
The berm, which is the top of the excavated edges of swales can have functional plants put in. To form a windbreak at a higher elevation, trees and hedging plants can be planted.
For added visual aesthetics, low growing, shallow root plants can be planted along the top edge. The reason to use shallow root plants are to ensure that the roots aren’t penetrating too deep into the soil as they would wind up in stagnant water leading to root rot.
Ditch the Traditional Mulch for a Living Mulch
A living mulch can be considered the lazy gardeners approach to mulching, and it anchors better because it has roots to anchor it into the soil. These are ideal for use on slopes, but they aren’t suited to all types of gardens.
Like any living plant, they need nutrients, and what you don’t want is your living mulch to out compete your plants for nutrients. As an example, in a vegetable garden, you could wind up growing more ground cover crops than edible plants.
How to Keep Mulch in Place with Dogs Running Loose
Dog owners have a harder time than most to keep their garden in good shape. Any type of mulch can be easily devoured by even the smallest of pooches, and not all types are easily digestible, such as wood chips.
To keep mulch in place when dogs are running around the garden, it’s essential to train them, offer plenty of alternative chewy goodies, and to secure the mulch with a physical barrier, such as mesh netting, or chicken wire.
Depending on how determined your dog is, you may need the barrier to be quite high to prevent them jumping over it. With training, a small perimeter barrier can be enough to let the dog know not to cross the boundary line.
Most dogs can be trained to stay within boundaries. Until yours is trained, a physical barrier may be needed. Particularly if you are using wood chips or shredded bark that can cause digestion issues.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.