Mulch is an essential component of gardening and landscaping. This simple yet powerful material provides a range of benefits to plants, soil, and overall landscape health. From retaining moisture and preventing weed growth to insulating roots and improving soil fertility, mulch plays a crucial role in creating a vibrant and healthy outdoor environment. But with various options to choose from at your local garden supply store, which are the best to use?
To answer this, we sought out a consensus opinion from some of the top-ranked gardening sites and their mulch reviews. We came away with a list of the six highest and most frequently recommended or rated types across 10 expert websites. Don’t see your preferred mulch type on the list? Let us know what it is in the comments below!
1. Shredded Bark
Shredded bark is sourced from cedar trees, pine trees, and other materials. It is one of the most popular and inexpensive types of mulch. It is ideal for sloped areas as it decomposes slowly and is eco-friendly. notes that because shredded bark can deplete nitrogen from the soil, you should consider using organic fertilizer to maintain plant health in nutrient-poor soil.
Using bark as a base for permanent trees, shrubs, and small greenery in your garden has many benefits. It provides insulation, retains moisture, and helps to prevent weed growth. However, it is important to only use this type of mulch once you have carefully planned out your garden layout. Keep in mind that removing bark can be a time-consuming process, so it is best to make sure you are committed to your garden design before laying it down, advises .
When composed of hardwood shredded from trees like maples and oaks, this durable mulch compresses over time to prevent it from blowing away or eroding. Its longevity makes it perfect for inclined areas and gardens in moist regions. Shredded bark that is rich in carbon is excellent for trees and shrubs, adds . Just be mindful that it is not as ideal for .
2. Compost
Composted mulch, a nutrient-rich and sustainable option, is typically created from a combination of fruit and vegetable waste, leaves, , and aged livestock manure. This type of mulch decomposes rapidly when made at home and may not offer all of the desired benefits when used alone. recommends applying a thin layer (2.5-5cm) of compost onto the garden soil surface, followed by a secondary mulch like leaf mold or wood chips for optimal results.
Compost resembles soil but has a darker color that many find appealing when placed around plants, says . This mulch material quickly breaks down to improve soil structure. It is a cost-effective option as rich compost can be made for free using grass clippings and leaves. Make sure your compost bin reaches high temperatures to eliminate weed seeds. Some cities offer free compost. Test a small area for potential weed seeds prior to spreading it in your garden.
Compost used for mulching deposits a substantial quantity of organic matter into the soil efficiently, enhancing soil quality and its ability to retain nutrients and water. However, it is not as effective at suppressing weed growth compared to wood or needle mulches. If using homemade compost as mulch, ensure that no herbicide-contaminated materials have been put into the compost bin, advises .
3. Straw
A byproduct of harvesting wheat and other grains, straw is typically free of weed seeds and readily available in grain-growing regions. However, it may be scarce and costly in other areas, says . Commonly used in and around strawberries, straw is known for its short lifespan, which coincides with the harvest of crops. It is also favored for establishing turf grass as it decomposes as the grass takes root. In colder regions, straw serves as a protective winter mulch for delicate plants, as it does not mat and poses a lower risk of suffocating them. However, it should be noted that straw is prone to blowing away and can be a potential fire hazard when dry. Furthermore, in cold climates, rodents may take shelter in straw during the winter, so it is not recommended to use it near trees and shrubs.
Straw is most effective as a gentle blanket for newly planted grass. It keeps the seeds secure and deters birds and rodents from feasting on them. Additionally, it traps moisture which is crucial for thirsty seeds. advises you to opt for straw over hay to avoid potential weed growth from hayseeds.
In the summer, keep vegetable gardens tidy with wheat straw. In winter, straw can be used to insulate against winter cold by applying a layer up to 6 inches deep. As the straw breaks down, it lowers soil nitrogen levels, so it’s wise to apply a nitrogen-rich fertilizer to replenish nutrients. While this mulch decomposes quickly, notes , it is readily available and cost-effective.
4. Stone and Gravel
Stone and gravel are common choices for inorganic mulch that can enhance the appearance of pathways, driveways, and decorative elements in a garden. While they offer aesthetic appeal and effective weed suppression with minimal upkeep, they may be difficult to install or remove, reminds . These mulches do not retain moisture well and can be hard to remove without replacing the topsoil. Therefore, it is important to thoroughly consider your landscaping needs and desires before using stone and gravel as mulch.
When properly installed, using stone or gravel makes for an extremely durable mulch. They are highly successful at preventing . This mulch also helps to retain moisture and prevent soil erosion, reports . In hotter climates, darker shades of stone or gravel may trap excessive heat, which can be harmful to some plants. Therefore, be mindful of what types of plants you choose to place your stones or gravel mulch around.
River rock, stones, and landscaping pebbles are generally more expensive than organic mulches. points out that a definite advantage is that they do not break down and do not need to be replaced yearly. On the downside, they do not improve soil quality over time. Stones can become hot in the sun, so use caution when using them as mulch in certain settings. They are commonly used in rock gardens and cacti arrangements. If using rocks in areas where plants won’t grow, such as under a deck, cover the soil with landscaping fabric to prevent weed growth. When using stones or river rocks as mulch, consider factors such as proper drainage, choosing the right size stones, and monitoring soil temperature. Regular maintenance, such as removing debris and checking for weed growth, is important for maximizing the effectiveness of stones as mulch in garden landscapes.
5. Rubber Mulch
Recycled rubber material is commonly used to create rubber mulch, which is primarily used for pathways and ground cover rather than garden beds. It is a long-lasting option that does not enhance soil quality, but it does serve as a weed barrier and inhibits fungal growth. Unlike wood mulch, rubber mulch does not absorb moisture and is effective at retaining soil moisture. It is a highly recommended option for and walking trails, reports , providing both soil protection and a springy surface.
Recycled rubber shreds and chips have been utilized as mulch in high-traffic areas, playgrounds, and other locations where a durable and long-lasting product is required. Its weight prevents it from being blown away. In playgrounds, it provides a soft landing surface for children and helps prevent weed growth. points out that this type of mulch has become less popular in recent years due to its high cost for installation (requiring two to four inches to be effective), tendency to accumulate organic matter and weeds that needs to be removed at least seasonally, and difficulty in removal for other purposes. Additionally, while it takes a long time to decompose, the breakdown of this mulch can release harmful chemicals and heavy metals into the surrounding environment.
Rubber and synthetic mulches are a durable and effective option for weed control in gardens, says . Made from recycled materials, these inorganic mulches are considered to be environmentally friendly. However, they do not provide nutrients to the soil and can disrupt its balance. There is also a risk of heavy metals and toxic chemicals leaching into the soil and groundwater, potentially harming plants and the environment. Consider the advantages and disadvantages before choosing these mulch types for your garden.
6. Pine Needles/Straw
Pine needles, also known as pine “straw,” are a very popular mulch choice in the southern regions of the U.S. because of their lightweight and natural appearance. notes that these needles are naturally acidic and break down slowly, making them ideal for mulching around plants that thrive in acidic environments. They are particularly effective on slopes during heavy rain, as they are less likely to wash away. Harvested from pine forests, pine needles are a renewable resource that can be a bit tricky to lay down neatly. As they age, they may turn a less appealing silver-grey color. Bale sizes can vary and may contain debris such as sticks and leaves.
Pine straw mulch is a colorful and effective option for controlling weeds. It is lightweight, easy to spread, and offers superior coverage. Additionally, pine straw mulch provides valuable nutrients for the soil, although it decomposes quicker than some other mulches and needs to be replenished more often. It is important to note that pine straw is susceptible to being blown away by strong winds due to its lightweight nature. Despite this, it is a cost-effective mulch choice, reports , especially when needed to cover a large area.
Long-leaf pine needles are ideal for use around trees, shrubs, and perennials that thrive in acidic soil, like Japanese maples, witch hazel, and delphiniums. Their reddish-brown color adds a natural touch to wooded areas. For maximum coverage, be sure to fluff the straw gently when applying it, advises .
Sources used for our list:
Note: This article was not paid for nor sponsored. StudyFinds is not connected to nor partnered with any of the brands mentioned and receives no compensation for its recommendations.