As we know, mulch is any material placed atop soil in a garden to enhance the wellbeing of both the soil and plants. It may be organic or inorganic. In our last post, we looked at the benefits of using mulch – today we address safety issues inherent in its use.
Inorganic mulches include geotextile matting, pebbles, landscape fabrics and plastic mulches. These deteriorate over time, are tedious to install, limit the penetration of water to the soil, and rarely look natural or aesthetically pleasing.
Organic mulch is a much superior product. Organic mulch is derived from natural plant materials that naturally decompose with the passing of time. During the decomposition process, organic matter and nutrients are added to the soil, and beneficial fungi and bacteria are enhanced in the soil. Pathogens which cause disease in plants are inhibited.
There are many types of organic mulch, and these include shredded bark, hay, sawdust, cocoa shells, grass clippings, leaves, and compost.
It is important to know that mulches, soils, compost, and potting mixes can be harmful to human health if not handled safely. This is due to the potential presence of the microorganism Legionella, which can cause pneumonia and other serious illnesses in humans if the organism is inhaled or transferred from hand to mouth; there are also serious implications if bacteria enter the body via a cut on the skin (tetanus infection can result from soil exposure in unvaccinated people).
Legionella cannot be transmitted person to person, or from animal to human. If Legionella infection occurs, it will do so after between two and ten days from exposure. Symptoms may include chills, fever, cough, aching, appetite loss, tiredness, and gastrointestinal upset. Medical attention is required as this is a serious disease which can be fatal if not treated promptly. If treated quickly and properly, it is quite simple to cure. Some people will only experience a minor illness; severity depends on age, severity of infection, and general health and immune response.
How to Handle Mulch Safely and Avoid Legionella Infection
Many people are potentially exposed to this organism when gardening, yet very few develop legionella infection. With these simple precautions, mulch and compost are very safe to use and can only enhance the health and appearance of your garden.