Dallas Morning News – October 5, 2017
Mulches – Some Better than Others
Shredded cedar – one of the best mulches.
Mulch is a blanket – an organic material that is applied to bare soil around plants. Effective mulches include shredded hardwood bark, pine needles, coarse compost, and shredded native tree trimmings. Shredded native cedar is the best of all. Mulching helps hold moisture in the soil, controls weeds and buffers soil temperature. It also protects and stimulates microbes and enriches the soil with nutrients as it decomposes.
I do not recommend plastic sheets or weed blocking fabrics. These artificial materials provide nothing beneficial. Plants roots can actually cook from the heat buildup. Plastic also fouls up the flow of oxygen in and carbon dioxide out of the soil. Nothing compares to a thick layer of shredded organic material. Lava gravel is the only possible exception. It works almost as well and helps to keep the neighborhood cats out of the beds.
Shredded hardwood bark – one of the better mulches.
The best mulch is recycled plant material (leaves, twigs, spent plants, buds, bark, flowers and other plant debris) that grew on your property. That’s the natural way it is done in the forest and on the prairie.
The second best choice is purchased shredded native cedar. The fresher, the better with cedar mulch. Freshly cut cedar has more oil, which provides fragrance and repels insects. Repelling insects is a nice side benefit, but the primary purposes of mulch are to protect the soil and help build humus. All parts of all cedar trees make excellent mulch. A mix of trees in the shredded mulch is also fine.
Third in line is shredded hardwood bark. Like the shredded tree trimmings, it holds in place well and breaks down properly. Then there is a group in the middle that includes cypress that is not high on my list because it does not break down well. We want the mulch to break down. That’s what creates the true natural food for feeding microbes and plant roots.
Pine bark mulch will not behave itself – one of the reasons I don’t like it.
Pine needles makes good mulch but look a little out of place when used on a property where no pines are growing. I’m not at all a fan of shredded rubber products, dyed wood, cypress or pine bark. It’s interesting that the most popular mulch, pine bark, is not very good at all. First, it won’t stay in place – it washes and blows away. What does stay breaks down into a mucky material that does help plant growth. Pecan shells also move around too much and fresh shells can attract fire ants.
Some companies grind the rough textured shredded tree trimmings into a finer textured, prettier product but the material right out of the tree care company’s grinder is fine for all plantings other than very small plants.