Gardeners are being urged to take extra care following 10 people in Christchurch contracting Legionnaires' disease.
Two people are in hospital with the disease, suspected to be from potting mix.
One of those hospitalised are fighting for their lives.
Canterbury District Health Board has confirmed that all 10 cases were reported in the last week.
Legionnaires' disease is caused by a bacteria and is a severe form of pneumonia, which can often make the disease difficult to detect.
Gardeners are being advised to wash their hands regularly, wear gloves and be careful when opening new bags of potting mix.