Pine Straw vs. Mulch: Which is the Best Choice for Your Landscaping?

No landscape is finished without a mulch layer, but mulch is far more than window dressing in a garden. When you mulch planting areas, you’re partnering with Mother Nature to nourish soil and all the life that exists within it. As you tackle mulching, you’ll have to decide what material to use, and that’s when you’ll likely face the question of mulch vs pine straw.

Pine straw and mulch aren't really two separate things. Mulch refers to any kind of soil covering, including pine straw, shredded bark, leaf mold and composted manure. In order to know if pine straw is right for you, what you want to know about pine straw vs. mulch is how pine straw interacts with soil, plants, water and all the other living parts of a landscape.

What Is Pine Straw?

Pine straw is simply the dried pine needles that fall from pine trees each year. (Think of them like fall leaves, except they can fall in spring and summer, too, depending on the type of pine and where you live.) When those needles are gathered and used as mulch, it’s known as pine straw.

In the Southeast, pine straw is the No. 1 mulching material for landscape plantings. The pairing of pine straw with azaleas and camellias is iconic in Southern culture, right up there with sweet tea, divinity and Friday night football.

Longleaf pine is the Rolls-Royce of pine straw, with long, reddish needles. Loblolly and slash pines offer shorter, browner needles. White pine needles also form shorter pine straw, but work well for mulch. Shorter needle types may break down faster than longleaf needles and are more prone to shift on a slope, but otherwise provide the same pine straw qualities.

The Benefits of Pine Straw

Like all mulches, pine straw moderates soil temperature, helps suppress weeds and slows water evaporation from soil. Pine straw allows water and air to filter easily to soil, while preventing erosion and protecting soil from developing a hard crust from rain and drying. With crops like berries, melons and tomatoes, pine straw mulch helps keep fruit from developing mold or mildew.

When first applied, pine straw is fluffy, but over time needles interlock and mat down, staying in place through heavy rains, even on slopes. Pine straw is lightweight and comes in bales that are easy to move and apply.

As a mulch, pine straw decomposes slowly, outlasting other mulches because of the resin in the pine needles. That decomposition helps to build and improve soil over time, recycling nutrients and maintaining organic matter in soil.

Pine Straw Is Sustainable

Because pine straw is the natural byproduct of pine tree growth, it’s a sustainable resource. No trees are destroyed to create pine straw. At commercial operations, pine straw is mostly raked by hand and placed into wooden boxes for baling.

Lightweight pine straw bales create less of a carbon footprint to transport. Twenty bales of pine straw equal approximately 5 yards of shredded bark mulch, which is roughly four scoops with a front end loader at the bulk mulch yard. That amount usually needs a large dump truck for delivery, compared to a full-size pick-up for the 20 pine straw bales. One 40-pound pine straw bale typically covers about 100 square feet of planting area with a 2-inch-thick mulch layer.

Mulch Basics

Mulch fills three key roles in a landscape. It helps to suppress weeds, moderates soil temperature and slows water evaporation from soil. Two main types of mulch are available: inorganic and organic. Inorganic materials break down very slowly over time or not at all. This group includes stones, rubber and plastic. Inorganic mulches tick the boxes of what a mulch should do, but don’t help nourish and build soil.

Organic mulches break down over time, adding organic matter to soil and feeding the microbial life in soils known as the soil food web. This network of microorganisms helps plants to grow by enhancing the ability of plant roots to absorb water and nutrients. Examples of organic mulch include pine straw, shredded bark, wood nuggets, bark fines, dry leaves, grass clippings, straw, compost and newspaper.

Local and regional organic mulch sources exist, too, including things like cotton burr compost, salt hay, zoo doo compost, worm castings, composted seafood byproducts, mushroom compost and even small seashells. Learn what industries are in your area to discover if there’s a mulch byproduct. Local products are usually cheaper than other mulch sources and offer a reduced carbon footprint.

Pine Straw vs. Mulch

Pine straw is becoming more widely available throughout the Northeast and Midwest as Southern pine straw companies sell online. Regional mulch suppliers are also transporting pine straw to box stores or independent garden centers in non-southern areas.

To understand if pine straw makes sense for your landscape, compare pine straw to a typical shredded bark mulch that’s double-ground. You can expect double-ground bark mulch to last one to 1.5 growing seasons, on average. Pine straw breaks down more slowly, lasting up to two years.

At the outset, the cost to put down a 2- to 3-inch layer of either double-ground shredded bark or pine straw is similar. Cost savings come into play in the second and subsequent years. With bark mulch, you usually have to add more mulch to the entire landscape, while with pine straw you just need to freshen up areas that have become thin or bare. Pine straw mulch is also easier to spread, creating less of a backache than shredded bark mulch.

In the bark mulch vs. pine straw debate, each material also offers distinct disadvantages.

• Both pine straw and shredded bark are flammable. Don’t use these mulches near homes in wildfire prone areas. Also avoid using them around fire pits.
• Bark mulch can host artillery fungus, which “shoots” tough-to-remove black spore masses that stick to siding, cars and other surfaces.
• Lightweight mulch of any kind can float away in heavy rains. Bark nuggets are notorious for their buoyancy.
• Some gardeners report that in windy areas, pine straw readily blows away.

Mulch vs. Pine Straw—Myths

Improve your mulch IQ by learning some common misconceptions about mulch.

• Pine straw makes soil more acidic. Not true. While actual pine needles are acidic, they don’t shift soil pH.
• Bark mulch attracts termites. Not true. Termites don’t feed on mulch made from wood. Any mulch creates conditions termites like: cool, dark and damp. University research shows that termites consumed more cardboard in bait stations beneath inorganic mulches like pea gravel than wooden mulches.
• Pine straw attracts snakes. No firm verdict. The pine straw itself doesn’t attract snakes, but can create an environment where creatures a snake likes to eat will live. Pine straw is also easier for snakes to burrow in.
• Pine straw houses palmetto bugs. True. In the South, a thick pine straw layer provides the ideal environment for these large outdoor roaches to reproduce. University researchers suggest keeping a pine straw layer thin for the first foot extending away from a home’s foundation, and consider applying roach control products in a band covering 3 feet extending from the foundation.

Pine Straw Application Tips

• Timing. In northern regions, you don’t have to wait for soil to warm in spring to apply pine straw. Apply it as soon as soil is workable.
• Depth. With any mulch, always focus on total depth when applying. Aim for a total depth of 2 to 3 inches, including existing mulch, as you add new mulch.
• Refresh. Add pine straw mulch when existing mulch is thin or reveals soil beneath.