Different mulches have different uses. Organic mulches decompose (some faster than others) requiring replenishing, and that can get pricey. Inorganic mulches such as plastic, stone, and rubber mulch are the more expensive options, but the cost is countered by the longer lifespan.
Explore These 10 Mulch Alternatives
1 – Cardboard and Newspaper
Cardboard and shredded paper can be used as a mulch alternative, just as you can add them to a compost pile as your brown material (because they were once, a part of a tree). They can enrich the soil with some nutrients, but on their own, they won’t do much good.
These materials are best used as amendments to other types of organic mulches. To use these as mulch, you’d apply cardboard and newspaper as the base layer, then add another alternative mulch over the top of it.
2 – Rocks, Gravel, or Pebbles
These are your stone mulch options. While these do last longer, the size of the stones or rocks matters. The smaller the pebbles or gravel, the sooner they can be driven into the soil.
The weight of heavy rainfall can cause smaller stones to sink. Larger rocks are the longer-term option that requires very little maintenance, although when installed on slopes, it’ll take some additional steps to keep mulch in place regardless of its weight.
The potential pitfall of using rocks as mulch is that no beneficial nutrients are being added to your soil. All stone mulches do is prevent insects nesting in soil, and stave off mold and fungi growth. ‘
The premier of rock mulches is pumice because it’s highly porous. Air and water can flow through to the soil without hindrance.
3 – Leaf Mold
Leaves and grass clippings can be good for mulching, but you need to have a good eye for details to check for signs of disease and know the trees the leaves are from. The fastest leaves to decompose are those from deciduous trees that fall in the autumn. Thicker leaves will need to be shredded first.
Leaves are good for the garden whichever way they are used. The preferred way to use them as mulch is to make a leaf mold.
You can do that by collecting loads of leaves, bag them in a black refuse bag, pierce several small holes in the bag for drainage, and then leaving it somewhere for up to a year. Mixing in some grass clippings with the leaf litter speeds the decomposition process up and increases the nitrogen content in the leaf mold.
Without including grass clippings, nitrogen content would be low, but the leaf mold would be high in carbon and several minerals transferred from the tree. If you don’t need mulch to feed nitrogen back to your soil, skip the grass clippings and make pure leaf mold.
4 – Pine Needles
Pine needles are the likes of those found on Christmas Trees. The cultivars are mostly fir trees, hemlocks, ‘true’ cedar trees, pine trees, junipers, and redwood.
Each of these has thin branches with clusters of needle-like leaves protruding from them. They’re all rich in organic matter that works a charm when added to compost, left on grass, or laid on flower beds. Just be careful of soil acidity as green pine needles are almost always acidic.
Don’t use fresh leaves as mulching material to avoid acidifying your garden soil. Yellow pine needles and those that have decayed to the point of browning will have lost most of the acidic content.
These can be applied to garden beds as they are – or shredded to make a leaf mold. The process takes longer because they are thicker.
5 – Hay
Hay and straw are affordable mulch alternatives. There’s more nutrients in hay though so stick with that and don’t use straw. Straw is only good for weed suppression. If that’s all you need your mulch to do, go ahead and use straw.
For nutritional value, hay is where it’s at and it becomes even cheaper when it can’t be used as animal feed, such as if it’s found to contain ragwort, or it’s begun to spoil. (Any type of organic mulch can get moldy). Even rotting hay and straw can work as mulching material.
What to be careful with are seed germination, and pesticides. Many farmers will treat their hay fields with pesticides and herbicides to protect them until harvest.
When that’s the case, you don’t want to use treated hay in your garden beds as the chemicals will leach into your soil, putting your crops at risk.
6 – Shells, or Nut Hulls
Seashells, eggshells, and all types of nut shells make hardy mulch materials. As can the shells of coffee beans (coffee bean chaff). They’re a bit like the rock types in that they take ages to decompose.
Eggshells, (used as they are) are sharp enough to deter slugs and snails from your plants. They also leach an abundance of calcium back into the soil, as do crushed seashells.
For those who go through lots of whole nuts, the hulls/shells are great mulch alternatives. The woodier they are, the better.
The best are the heavier shells from the likes of almonds, chestnuts, hazelnuts, and walnuts. These are long-lasting, but given you’ll likely have them in smaller quantities, you’ll be short on supply for garden beds. Instead, use these as toppers for your planters.
Mulch is as good for plants as it is in your garden soil. You could also mix a blend of different shells for higher quantities with cost-savings.
7 – Wood Chips
Wood chips are terrific for mulching and can last anywhere from 4 to 7 years if you don’t mind the loss of aesthetics. As the wood chips decompose, they begin to lose their aesthetic appeal after just a couple of years.
The first mulching will be the most expensive as you’d be building several inches in layers. After a year, you’ll be able to turn it with a rake, and then the following year, if you don’t mind the look of it, keep it.
If it looks terrible and is ruining your landscape, adding an inch or two will bring it back to its former glory. As a guideline, the initial layer of mulch should be up to 3” thick, then add at 1” per year as the general decomposition rate is 1” per year.
8 – Green Mulch/Ground Covering Plants
Green mulches are low-growing ground-hugging plants. Each of the following has a maximum height of under 10 inches…
- Armeria – 8 inches
- Brass Buttons – 6 inches
- Bunchberry – 6 inches
- Crested Iris – 9 inches
- Epimedium – 8 inches
- European Ginger – 4 inches
- Sedum – 3 inches
- Hens and Chicks – 4 inches
- Lamium – 8 inches
- Creeping Phlox – 4 inches
Do be aware that each will spread – some faster than they grow, and often rapidly. You may not need a lot, or if you use a spreading variety, you could spend more time cutting them back to keep their size in check.
As a mulch, ground-covering plants will suppress weeds, and lock in moisture. The risk is replacing the weeding chore with pruning.
9 – Rubber Mulch
Rubber mulch has a premium price tag attached, despite providing no nutrient value to your soil. The core benefit is that it’s maintenance-free.
Once it’s down, you’re done. It won’t decompose in your lifetime. You can get these in different colors, and you can also lower the cost while reducing your carbon footprint by mixing rubber mulch with wood mulch.
10 – Plastic Mulch
Plastic mulch that is either aluminum-coated or clear is the best mulch for repelling bugs because of how it reflects sunlight. Bugs get confused, so they’re deterred from straying near your plants.
Because of how heat is affected by plastic mulch, it is unsuitable to use near heat-sensitive plants. Stress can overwhelm tender plants resulting in peculiar behavior such as leaves wilting, discoloration, and stunted growth.
The Golden Rule of Mulching: Never Use Landscape Fabric!
The one thing never to reach for near any plants is landscape fabric. It looks ugly, does not suppress weeds, and doesn’t allow much water to flow through the netting into the soil beneath.
The majority of weed seeds get spread by wind, germinate, and then root in the soil. Once anchored, it’s next to impossible to get entire weeds out without ripping up the landscape fabric. It’s a waste of money buying it, and a waste of time installing it.
The only useful time is when you’re installing it beneath pavers, or decking, but around plants, fabrics do more harm than good.
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.