In most social situations, starting a conversation about mulch is a non-starter and a great way to ensure time spent alone. That said, this is a blog about landscaping, and delving into the topic of mulch is wonderfully appropriate. In fact, I confess to being something of a mulch aficionado– a good thing to be when one is a landscaper.
Wonderful World of Mulch. There are lots of choices when it comes to mulch. Perhaps it is not the most glamorous aspect of your landscape, but it can make or break the look and feel of the project. It is the final coat of paint in the landscape, and done poorly can diminish all the positives. In short, mulch matters.
What is mulch? In short, mulch is a non-living groundcover. It can be divided into two broad categories: organic (shredded bark) and in-organic (stone). There are many options within these categories, and your choices will be guided by the needs of your particular landscape and your aesthetic goals.
Why mulch? An obvious question with good answers. First, mulch aesthetic value– it provides a field of background color to contrast or highlight flowers, foliage and features. It helps hold the design together and maintain aesthetic flow. It helps define planting beds and create a clear contrast with turf. It can be an attractive element of your landscape by itself by introducing colors and textures.
Mulch can help suppress some weeds or at least make them easier to pull. Many weeds will happily grow in mulch and like the loose texture. That is their undoing, as pulling weeds out of mulch is a much easier task than pulling them from soil. Mulch also helps retain moisture in the soil and can protect roots from excessive heat and cold. Finally, mulch can help add organic matter to the soil over time and can influence soil Ph by making it more acidic or more alkaline.
Kinds of mulch. There are lots of choices… some good, some bad, some common, some exotic. We’ll start with the major players:
Hardwood Mulch. Good hardwood mulch should be made primarily of the bark of hardwood trees. The hardwood mulch we use has been shredded at least three times, which gives it a fine, almost fibrous texture. In addition to being easy to work with, this mulch tends to knit together and stay in place, which is handy on some slopes and along walkways & driveways. This is by far the most common type of mulch in Louisville, and is a great general-purpose choice. It is usually sold in bulk, but can be purchased in bags for smaller applications.
Poor quality hardwood mulch often has a low (or non-existent) bark content. Cheap hardwood mulch can contain anything from tree limbs to shipping pallets and scrap lumber. It usually has a chunky look and feel, stays loose and uneven, and floats/shifts easily. In addition, cheap mulch can attract termites (which will not eat bark), and can contain unwanted fungus, such as artillery fungus, which can cause expensive damage to siding and windows. Sometimes it is sold as playground mulch, which seems odd as it can contain sharp edges, splinters and, in some cases, scrap metal or nails. Use with caution.
Hardwood mulch comes in a variety of colors. The higher quality mulch is usually available in brown or black, while cheaper undesirable mulch can include red, green & blue colors. Tree bark is naturally brown, and is sometimes enhanced with an organic colorant. Black hardwood mulch should feature a non-toxic dye and is usually aged before sale. It is difficult to safely dye bark mulch black, and for this reason it is more expensive. The red/blue/green varieties of mulch are made of core wood and are relatively easy to dye. We avoid these types of mulches in favor of more natural looking varieties.
A producer in Lexington, KY (Creech Services) makes an attractive hardwood bark mulch product that is mixed with high quality compost made from thoroughbred horse manure- good for almost any garden.
Cypress Bark Mulch. This mulch comes from the bark of cypress trees, often from Florida. It tends to be more reddish-orange in color and has a pleasant smell. It has a distinctive look and lasts a long time. One drawback is that it blows easily when dry and can be displaced by wind/water/mower discharge. Grass clippings are extremely difficult to remove from cypress mulch. Sometimes this is sold in bulk, but usually sold in bags.
Pine straw. This type of mulch is gaining in popularity. It has a nice brownish color with hints of red/orange. Sometimes it even comes with pine cones! Care must be taken when installing pine mulch to achieve consistency and a clean line along bed edges. The pine needles seem to do a good job suppressing weeds. The needles fade to gray over time (a season) and need to be refreshed or replaced. Over time, pine straw can benefit acid-loving plants, such as azaleas, rhododendrons, and hollies. Pine straw comes in smaller bales and can be a little pricey.
A new product called “Softscape” mimics the look of pine straw but is made from hardwood. Although more expensive, it has the benefit of retaining its color much longer than pine straw.
Other mulches:
Leaf mold or compost. Chopped, composted leaf mold makes for a natural look for a woodland setting. Hey, this is what Mother Nature would provide, right?
Pine bark. Comes in a variety of textures ranging from fine chips to large nuggets. It is long lasting (3 years) and drains easily. The finer varieties seem to work best, and are great around acid-loving plants.
Grass clippings. Great for the organic gardener if used with caution. Never use grass treated with weed killers, and be sure to keep the mulch layer at two inches or less. Clippings will decompose and add organic matter to the soil.
Stone/gravel. Lots of choices here, ranging from Mexican Pebbles to fine grit. The effect can be striking. Stone is long lasting and attractive, but has some drawbacks to consider. First, it usually requires the use of landscape fabric to keep the stone on the surface. The fabric does not control weeds very well (weeds will happily grow between the stones), and can be a bear to install. The fabric will inevitably heave to the surface creating a maintenance issue. Also, stone mulch is an absolute nightmare to remove (think expensive) once installed. Keep this in mind if you like to try new looks.
Exotic mulches:
Pine cones; buckwheat hulls, hemlock bark, oyster shells, licorice root, and cocoa, to name a few, all make striking mulches. They can be difficult to obtain but provide a truly unique and beautiful look. In small gardens these mulches can be very effective.
What about that everlasting rubber mulch stuff?
Buh. Rubber mulch makes me shudder. Sure, the color (allegedly) never fades, and it (allegedly) won’t decompose. But do you really want to mulch with a petroleum product? I don’t know what this stuff is made of– old tires? Might as well mulch with shredded water bottles or plastic shopping bags. I’ll admit I am not looking forward to the day when I have to remove this stuff from a landscape. I’m sure it will be unpleasant (and cost a fortune). Helios Landscaping will never install rubber mulch. As far as I’m concerned the stuff is toxic waste and a form of pollution. If that makes me a snob, then so be it.
