Take care when using potting mix and compost

Thursday October 24, 2013

​Canterbury Medical Officer of Health Dr Ramon Pink says that gardeners need to take care when handling potting mix or compost.

​A Coroner’s report finding potting mix was the likely cause of death of a Canterbury woman is a timely reminder of the importance of taking care when using potting mix and compost.

Coroner, Richard McElrea, found a Christchurch woman in her early 60s died of Legionnaires’ disease after contracting pneumonia caused by Legionella longbeachae – a bacteria, which is found in potting mix.

“Labour Weekend is a popular time to get back in the garden and plant vegetables for summer. Enjoy your gardening by all means but please make sure you avoid inhaling the dust from potting mix or compost as this can be dangerous,” Dr Pink says.

“It's important to follow the five simple steps when handing potting mix or compost to help reduce the risk of developing Legionnaires' disease.”

The five simple steps are:

  1. Open potting mix bags carefully using scissors, rather than ripping them.
  2. Wear a disposable face mask and gloves and open the bag away from your face.
  3. Do your potting in a well ventilated area outside.
  4. Dampen down the potting mix or compost with a sprinkle of water to stop the bacteria from becoming airborne.
  5. Wash your hands thoroughly after handling potting mix and doing any gardening.
The bacterium Legionella can be present in potting mix and compost. It thrives in warm, moist conditions and can cause a severe, even fatal disease when contaminated particles or droplets are inhaled.

“Anyone can catch Legionnaires’ but certain people are more vulnerable including people over 50 years of age, those with a long-term illness, particularly lung disease, people with low immunity and smokers.”

Symptoms of the disease may include dry coughing, high fever, chills, diarrhoea, shortness of breath, chest pains, headaches, excessive sweating, nausea, vomiting and abdominal pain.

Anyone who gets these symptoms should see their general practice immediately, and let them know they have been handling potting mix or compost recently.

Page last reviewed: 01 November 2013