SELECTING THE RIGHT MULCH: A strictly organic leaf mulch is put down in the backyard in preparation to grow an organic community garden.

“Mulch will hold moisture in the soil, especially when it rains, which is one of the environmental benefits to using a mulch.” — Pat Raglin. 

“It was so difficult to enjoy the trees and flowers when I was  so aware of all that I had not yet done – pruning, weeding, transplanting, mulching, composting, tagging, when I was doing the work myself, I was happy, free.” —  Jay Neugeboren. 

“We do not inherit the earth from our ancestors, we borrow them from our children.”  — Native American Proverb. 

September is cruising right along and the warm temps of summer seem to be lingering, but the cool temps of fall are definitely on the horizon as the first day of fall is Sep 22. Welcome fall as you complete  landscape projects with mulching each landscape bed. Mulches offer many advantages!

Many different mulches (organic and synthetic) are available today which provide curb appeal, reduction of soil water losses, suppression of weeds, and protection against temperature extremes. Mulches also provide other benefits including the reduction of soil erosion and crusting, and the improvement of water infiltration into the soil profile. For example, when water droplets (rainfall or irrigation) make contact with the bare soil, this impact causes the soil particles to scatter in all directions which results in soil erosion, crusting, compaction and slow water infiltration. Many mulches buffer this impact from such droplets providing more favorable growing conditions and positive visual results.

In addition, mulches improve the soil structure which is critical in the growth and development of plants. As organic mulches decompose, they provide organic matter that encourages the soil particles to aggregate or come together into larger aggregates. These larger aggregates increase soil aeration and improve moisture conditions and availability. Such conditions favor additional root development and improved biological activity which further improves soil structure.

A good mulch will be economical (cost effective), readily available, easy to apply, static in movement, supply organic matter to the soil, and is free of weeds, insects, and diseases. And, it will suppress weeds, conserve soil water, and moderate soil temperatures. A super-mulch does not exist and all mulches tend to have both positive and negative qualities in the landscape. Organic mulches offer many benefits.

Straw, shredded leaves, pine needles, and wood chips are effective in curb appeal and serving as insulating blankets in winter, but they slow the process of soil warming in the spring. Also, pecan shells and cottonseed hulls can be used for mulches. However, pecan hulls attract insects pursuing any minute pieces of pecan that might be left in the hull and birds will scatter the hulls as they search for these insects.

As the pace of falling pine needles increases, so do our efforts on the ground in cleanup. Rather than dispose of these valuable assets, it’s a good opportunity to use them to replenish our landscape beds and provide additional curb appeal. 

There isn’t a definitive answer in the selection of a particular mulch to use. But understanding the characteristics and features of the different materials which are available can help in the selection of the best mulch to use for a particular location and environment.

As a general understanding, wood chips, bark chunks, and pine needles are appropriate mulches for shrub beds or around trees. Fine mulches, such as bark granules and wood shavings are attractive when used in annual or perennial beds. Fine gravel or crushed stone mulches look most natural when used in rock gardens, xeriscapes or around the foundation. 

Commercial bark mulches are categorized based upon particle size including bark chunks (decorative bark), bark granules (soil conditioner), and shredded bark. Of these, bark chunks are the most persistent and desirable. However, some bark mulches may be toxic to young plants, especially if the bark is fresh or if it has been improperly stockpiled or mismanaged. Such toxins can be leached from the fresh bark with multiple applications of water, evaporated by thorough aeration through turning and rearranging the stockpile, and allowed to season for at least three months before using them.

Commercially-available bagged bark mulch products have been allowed to weather for long periods of time to remove any toxins and are least likely to harm plants. The most desirable characteristics of bark mulches include excellent resistance to compaction, minimal movement by wind action, attractiveness or curb appeal, and availability.

Wood chips are another mulching choice made available from many different hardwood and softwood species. Fresh chips have a higher carbon to nitrogen ratio which means that during decomposition they may temporarily reduce the supply of soil nitrogen available for plant uptake. Again, age any fresh chips for about three months before using them in the landscape. 

Pine needles have a most pleasing appearance and acidifying effect on the soil around acid-loving plants. They are available commercially and can be raked up from around pine plantings in the woods or off the lawn. Pine needles decompose slowly (but do discolor quickly in the south Georgia heat), are resistant to compaction, and are easy to work. They provide excellent protection and ornamentation around shrubs and trees.  However, if used in deciduous beds, the combination of fall leaf drop and existing pine straw mulch can be an undesirable mix thus creating more work to address in the fall clean-up process. 

Matching the mulch to the landscape bed (such as pine straw under pine trees) is most critical and should be done after considering all the options. The mineral or synthetic (inorganic) mulches will be discussed next time and do not contribute any beneficial organic matter to the soil as do the organic mulches but they can offer superb curb appeal and low maintenance. Always think of environmental compatibility and sustainability when selecting landscape mulches. Goodbye Summer and Hello Autumn! Fall is almost here!

“I lift up my eyes to the hills — where does my help come from? My help comes from the Lord, the Maker of heaven and earth.” Psalm 121:1-2. “Live in harmony with one another; be sympathetic, love as brothers, be compassionate and humble.” 1 Peter 3:8. “We know and rely on the love God has for us. God is love. Whoever lives in love lives in God, and God in him.” 1 John 4:16. “Teach me to do Your will, for You are my God; may Your good Spirit lead me on level ground.” Psalm 143:10.