Know Your Mulch

We often recommend mulch in our blog posts. While mulch might not be the complete miracle for whipping your yard into shape, it comes pretty close. The main goal of mulch is to improve your soil conditions, regardless of which type of mulch you use. Mulch does this in a number of different ways, including:

• helping keep soil temperature even
• preventing soil compaction
• protecting planting from lawn mowers and weed whackers
• sealing in moisture
• suppressing weed growth

In addition to these crucial functions, mulch just looks good and gives your yard a well-maintained appearance. In general, homeowners have two main categories of mulch from which to choose: organic and inorganic.

Organic mulches are comprised of materials that will naturally break down over time. We will go into each in more detail, but they include:

• bark
• compost mixes
• evergreen needles
• hardwood and softwood chips
• leaves, grass clippings
• newspaper /cardboard
• plant byproducts

Mixing any of these into your soil can improve the fertility of your soil, aid in aeration, and better your drainage as they naturally decompose. The benefits of this decomposition also come with the knowledge that you will have to replace organic mulch regularly over time if you wish to retain those benefits.

In contrast, inorganic mulches, do not decompose and require very little replacement, if any. Common inorganic mulches include:

• crusher dust
• landscape fabrics
• lava rock
• pulverized rubber
• rock
• stone

Inorganic mulches really shine when it comes to weed suppression and decoration. It’s worth noting that stone mulches both absorb and reflect heat. This can be helpful in spring, as it can warm the soil fast and help you get some pants in the ground sooner. During the dog days of summer, however, it can warm the soil too much. If conditions are also dry, this could put those plants in harm’s way. Be sure to water those areas extra well.

If you have decided to take the plunge and get started placing mulch in strategic locations around your yard, the next step is to decide which mulch (or mulches) will best suit your needs. To that end, let’s take a look at some different, popular mulch options.

Organic Mulch
As we mentioned above, organic mulches are mulches that provide benefits as they decompose, so they’ll need to be replaced regularly.

Bark, Nuggets, and Wood Chips
Bark, nuggets, and wood chips come in both hardwood and softwood varieties. They are dried and aged. Sometimes they are dyed (usually red or black), then packaged and sold in bags. For trees, shrubs, and perennial flower beds, you’ll want to stick with hardwood. For large trees and shrubs, you can opt for softwood, which is usually some variety of pine. Pine, in general, is a little more acidic, so it will take longer to decompose when compared to some other organic mulch options. If you are looking for mulch for walkways, you can check with your local municipality. Some will give you their freshly-ground mulch from public works clean up jobs… free of charge. This mulch is not dried or aged, so keep it to walkways. If you put it anywhere else, it will pull a tremendous amount of nitrogen from your soil as it decomposes. This will handcuff the growth of other plant life in that area.

Straw
Do you have a newly-seeded lawn? Straw from clean barley, oat, or wheat is a great light-mulching option. Straw mulch does a solid job keeping the new grass seed in place, while protecting it from rodents, birds, and other critters. As is decomposes, it soaks up moisture which is essential for seed germination. While they make look similar, straw and hay are not the same thing. Hay can contain seeds that could easily sprout in your garden. Using hay would be like intentionally planting weeds in your yard or garden.

Shredded Leaves and Grass Clippings
One quick and easy way to get mulch is to make it yourself by saving shredded leaves and grass clippings from your regular yard maintenance. Grass clippings are ideal for perennial and vegetable beds. You’ll want to turn them into the soil at the end of the season for maximum benefit. Shredded leaves, on the other hand, are good for garden beds, as well as around trees and shrubs. You’ll want to avoid spreading either on too thickly, which can lead to matting that has the potential to block air flow. Note: If you have used insecticides or herbicides on your grass, do not use those clippings for mulch.

Cardboard / Newspaper
If your main goal with mulch is weed suppression, then undyed natural cardboard and/or shredded black and white newspaper is a very effective organic mulch choice. For maximum benefit, start with two or three layers, then cover those layers with a heavier organic mulch, like shredded leaves or grass clippings. This will help keep the cardboard or newspaper in place. Avoid coated cardboard or colored newspaper. They take a long time to decompose and can possibly introduce toxic dyes to your yard.

Cocoa Chips
With a name that could just as easily live in your pantry, cocoa chips are known for their rich color and familiar scent. Made from cocoa bean hulls, cocoa chips are easy to work with and an ideal fit for any mulch application. Take care not to apply more than an inch nor to water too much in areas where you spread cocoa mulch. It decomposes more quickly than other mulches. It also comes with a higher price tag than many other mulches. You’ll want to get by with a once-yearly application if possible. You should avoid cocoa mulch if you have pets, as it contains the same byproducts in chocolate that can be dangerous to pets.

Manure
Used as a mulch, it is also a great fertilizer. Composted animal manure is rich in nutrients that plants just love. It works particularly well for vegetables. Note: cat, dog, and pig manure may contain organisms that can cause diseases in your plants. Further, fresh manure can burn the roots of your plants. Avoid all of this manure.

Inorganic Mulch
As we mentioned above, inorganic mulches are mulches that do not decompose and do not need replacing very often.

Rock
You can get mulch rock in a number of different forms, including: crushed gravel or crusher dust, lava rock, marble chips, and pea gravel. Because inorganic mulch doesn’t decompose, it is an ideal choice for walkways and paths. If you opt for stone, you’ll want to keep it away from plants, shrubs, and trees. Rock mulch does a poor job at retaining moisture, as compared to organic alternatives. Also, it retains heat, which can cause the soil to warm to unsafe temperatures for plant roots when the mercury rises in the thick of summer.

Landscape Plastic / Fabric
Landscape plastic can be tricky. It is made from polyethylene film, which is impermeable. This means that neither water nor nutrients can pass through it. Sure, this also means that it is a great weed suppressor, but it really should be considered just a short-term solution. Now, if your goal is to use it as a way to keep the soil surrounding your plants warm, you’ll also have to install some sort of irrigation system under the plastic to ensure the plants are getting enough moisture. You could also water the old fashion way… by hand. At the end of each growing season, you’ll want to remove the plastic; otherwise, it will deteriorate in the sun. This also means that you will have to replace it next year if you opt to use it again.

If you want a longer-term solution, landscape fabric is the way to go. It has the same weed-suppressing effect, but it is permeable, allowing air and moisture to pass through. Because of these advantages, you can expect it to come with a higher price tag than landscape plastic. To really get the most from your landscape fabric, place a layer of organic mulch across the top of it. Wood chips would be a great option.

Rubber
Durable and inexpensive, rubber mulch is made from recycled tires. For this reason, it is the perfect mulch for playgrounds and really not much else. It doesn’t decompose and since tires were originally made for a different application, they can contain toxins that work their way into the soil, undermining the health of anything trying to grow there.

Know When to Say When
Yes, you can have too much mulch. If you are piling up mulch around the bases of your trees and shrubs, you can start to have a problem with too much moisture collecting in the root zone, which can lead to root rot. Further, this technique is just asking for problems with rodents and/or insects. The ideal depth for layering mulch is about two-to-four inches.

In Conclusion
When it comes to mulch, you have a myriad of different options. The first step towards choosing the right one is knowing which mulch is most ideal for your application. When you have the right mulch, just follow recommended application directions to realize the full potential mulch can have on the appearance and health of your landscaping.

To get the most out of your landscaping, E.P.M. Lawnscape and Supply offers professional landscaping design and installation services in the Jackson, MI area. Feel free to contact us online or call us today at (517) 990-0110.