Skip To Content

    Special Safety Alert! Beware of Poisonous Mulch!


    It’s Spring, and everywhere you look there are articles about gardening. Most of them are full of ideas for a more colorful yard, but I’d like to add a tip that can actually save your life. You’d never expect something as dull as mulching to become a matter of life or death, but it truly can be.

    Composted wood mulch is full of benefits for your plants, but the same conditions that nurture nutrients can also result in dangerous chemical reactions. Here’s why, and how to prevent these problems.



    Under ideal conditions, hardwood mulch is kept in a holding container until it’s fully decomposed and safe to spread. However, if the mulch has too much moisture and not enough oxygen, then hydrogen sulfide, methane, ammonia and alcohol gases will increase rapidly and cause what experts call “sour mulch”.

    So how does this happen? Many homeowners attempt composting mulch after taking a tree down & are unaware of potential problems. You might do this yourself, or answer one of those Free Mulch ads that helpful locals put up to get rid of their overflow. Sometimes even commercial grade can revert back to dangerous off-gassing levels due to moist storage conditions.

    The best case scenario for “sour mulch” is sick plants and an unpleasant smell. The worst case scenario is a fast progressing, painful condition that can actually kill you. Hydrogen sulfide will burn your lungs and poison your bloodstream, with symptoms such as shortness of breath and weakness appearing in a matter of hours. The physical labor involved in spreading mulch means that you’re taking in extra large breaths full of these dangerous vapors.

    Stay safe by knowing the signs of “sour mulch” and how to prevent it. If you have a large mulch pile going, it’s crucial to turn it over and let it air out regularly. Stir it with a rake and avoid tall, impenetrable stacks. If mulch smells sour and vinegary, it’s gone bad and you should dispose of it immediately. If it’s already spread on your garden, then wash it down thoroughly with a hose. It’s easiest to avoid this problem entirely by using pine mulch, which is less prone to souring and is excellent for plants.

    If you’d like more gardening advice, I recommend talking to Kim & Anthony at Condurso’s Garden Center in Montville, NJ! They will always greet you with a smile and their knowledge and selection is unbeatable. Home Depot may be everywhere, but you can’t beat a Morris County family business for that personal touch! 

    Jacqueline Scura is a Top Selling Agent in NJ and has over 28 years of experience as a Realtor. Her unparalleled local Real Estate expertise and involvement makes her a resource for Morris County Real Estate Advice & New, Town Events and Information and Household Tips & Tricks. She specializes in Parsippany Real EstateBoonton Real EstateBoonton Township Real EstateDenville Real EstateMontville Real EstateRockaway Township Real EstateCaldwell Real Estate and Mountain Lakes Real Estate. Narrow down your search for Rentals or Condos and Townhomes on my site!

    Contact her with any questions at (973) 335-4600 or visit her website at“Like” our Facebook Page at
    Jacqueline Scura  |  RE/MAX First Choice Realtors  |  1160 Route 46 West, Parsippany, NJ

    Trackback from your site.

    Leave a Reply