Learn how to reduce your risk of Legionnaires’ disease with simple precautions when handling compost, mulch and potting mix.
Gardening is a rewarding way to spend time outdoors, grow fresh produce and keep active. Whether you’re planting a new garden, filling pots or spreading mulch around your landscape, a few simple precautions can help you enjoy these activities safely.
One potential health risk to be aware of is Legionnaires’ disease, a respiratory illness associated with Legionella bacteria that can naturally occur in soil, compost and potting mix.
Understanding Legionnaires’ Disease
Legionella bacteria are naturally found in the environment and may be present in soil, compost, mulch and potting mix. Gardeners can potentially be exposed when handling these materials, particularly when fine particles or dust become airborne and are breathed in.
There is no known method of eliminating Legionellosis from mulch, compost or potting mix during manufacture. These bacteria are not exclusive to any particular brand or type of growing medium. Their presence is a natural environmental risk, which means safe handling practices are important whenever you work with compost, mulch or potting mix.
Although the risk of becoming ill is low, taking sensible precautions can help reduce exposure and make gardening safer.
Important Safety Information
All our bagged growing media products carry warning labels with important information about safe handling and reducing the risk of Legionnaires’ disease.
Please read and follow the safety instructions on the packaging before use. We also recommend following the precautions outlined in this guide whenever handling potting mix, seed raising mix, compost or mulch.
Taking a few simple steps can help minimise exposure to dust and make your gardening experience safer.
Who Should Take Extra Care?
Anyone working with soil-based gardening products should follow safe handling practices. However, some people are more vulnerable to developing serious illness, including:
- Older adults.
- People with weakened immune systems.
- People living with certain chronic health conditions.
- Smokers.
Taking a little extra care when handling gardening materials is particularly important if you fall into one of these groups.
8 Tips for Safer Gardening
Follow these practical tips whenever you’re handling compost, mulch or potting mix.
1. Keep dust to a minimum
Avoid shaking, throwing or handling dry materials in ways that create airborne dust. Work gently and take your time.
2. Dampen materials before use
Lightly moisten compost, mulch and potting mix to help prevent dust from becoming airborne. Avoid creating unnecessary spray or splashing.
3. Open bags carefully
Open bags slowly and keep them away from your face. Avoid squeezing or shaking the bag, which can release dust into the air.
4. Wear gardening gloves
Protect your hands by wearing suitable gloves when handling compost, mulch and potting mix. Wash your hands thoroughly with soap and water when you finish.
5. Consider wearing a well-fitting mask
A suitable, well-fitting particulate respirator can provide additional protection when opening bags or handling materials that may produce dust. This is particularly worth considering for people at higher risk.
6. Water plants gently
Use a gentle watering technique for indoor and outdoor plants to minimise splashing and the disturbance of growing media.
7. Work in a well-ventilated area
If you’re potting plants in a greenhouse, potting shed or other enclosed space, ensure there is adequate ventilation and avoid allowing dust to accumulate.
8. Read product safety instructions
Check the warnings and handling recommendations on bags of compost, mulch and potting mix before use, and follow the manufacturer’s advice.
Know the Warning Signs
Legionnaires’ disease can cause symptoms similar to the flu, including fever, chills, muscle aches, headaches and a cough. Symptoms may develop several days after exposure.
If you become unwell after handling compost, mulch or potting mix, seek medical advice promptly and mention your recent gardening activities. If you develop worsening flu-like symptoms, a persistent cough or difficulty breathing, don’t delay getting medical attention.
Early diagnosis and appropriate antibiotic treatment are important for Legionnaires’ disease.
Enjoy Your Garden with Confidence
Gardening offers many benefits, and taking sensible precautions can help you continue to enjoy it while reducing potential health risks.
Remember to minimise dust, dampen dry materials, wear gloves and wash your hands after handling compost, mulch and potting mix. These straightforward habits can make a difference to your gardening safety.
Further Reading and Official Guidance
For more detailed information about safe gardening practices and Legionella bacteria, consult these New Zealand resources:
- Safer and Healthier Gardening — New Zealand Ministry of Health.
- Legionellosis: What You Should Know If You Work with Soils, Compost and Potting Mix — Ministry of Business, Innovation and Employment (MBIE).
- Safer Gardening and Legionnaires’ Disease — Go Gardening, Nursery and Garden Industry New Zealand.
For the latest health advice, refer to official New Zealand health guidance.
By following a few simple precautions, you can reduce potential risks and keep enjoying all the rewards of gardening.