Would You Read A Warning Label On Potting Compost?

 Legionnaires’ disease spores identified in some potting compost

I have always fancied the idea of living in an off-grid caravan in the middle of a field, a professional hermit if you like. The idea of living a solitary lifestyle tending to the garden without interruption and the trappings of modern living also seemed so appealing.

Until recently. 

I had what I like to call “A bit of a turn” just before Christmas and the thought of being anywhere but in a warm and dry home or even a hospital would have been a nightmare. 

I don’t really like talking about ailments but in this case and haven’t done sense I had my tonsils out when I was 7. I’ll make an exception here, so just pretend you’re in the supermarket queue and asked me how I am getting on.  

Initially I didn’t feel very well with a few cold symptoms so took myself to bed for a while. Which turned into ten days. After that time, I wasn’t feeling any better and I lost the ability to walk out of the bedroom unaided, so I had a feeling it was something more than a cold.  One ambulance journey to the hospital later it turned out I had pneumonia. I’d have never guessed I was in the vulnerable category but as I’m getting close to 60 maybe I am.

I had a week in my own quarantined room in the hospital as they did tests to see which strain of pneumonia I had, there are contagious and non-contagious types. It didn’t take me long to get institutionalised and I soon got used to the regular meals and around the clock attention from the wonderful staff. 

It turned out I had the non-contagious type (which didn’t surprise me as I don’t really come into contact with many people) so the facemasks came off and the doors were opened. This got me thinking, how did I get it if it wasn’t from someone breathing on me?

It’s pure speculation of course but I narrowed it down to two things that I did prior to having the “Turn” I was cleaning up old lamps with really fine wire wool the day before without a facemask and I was thinking some of the steel dust could have latched onto my lungs and caused an infection. The second theory- because that’s what this is, a theory- was that I opened an old bag of potting compost in the tunnel a few days before and maybe breathed in some of the fungal spores from the bag. 

There have been a few cases of people getting Legionnaires’ disease(L. longbeachae)a specific form of pneumonia which can be carried in water, especially water that’s warm such as in air conditioning, hot tubs, in soil, old potted plants and also in damp bags of unopened compost. 

The move away from peat based compost has given rise to a lot more varied products being used to bulk up the bags. The fungus is commonly found growing on dead leaves, compost piles and decaying vegetation and are all now being used in potting compost.  It’s generally harmless but can cause serious problems if too many spores get into the lungs. The spores could lead to allergic reactions, asthma attacks and hayfever-like symptoms

New Zealand and Australia have both a large gardening community and have historically used wood-based potting mix. In more recent years the UK and Ireland has moved away from peat-based mixes to wood-based ones to save peat lands. Along with this change, came an increase of disease from potting mixes. In North America, the commercial bags of potting media are still predominantly peat-based and research has seen fewer cases of the disease. The research doesn’t take products such as coir compost into consideration though as a peat substitute.

Warning Labels 

 A British study found that 4 of 22 brands of potting soil contained L. longbeachae. Some individuals who have suffered, either directly or indirectly are calling for warning labels to be put on products that could potentially cause the disease. 

Australia and New Zealand have had labelling regulations in place since 2003 and 2005 respectively. Labelling has not resulted in a decline of the disease and like me, most customers completely ignore the labels anyway.

There have been a few cases linking L. longbeachae to gardeners, so backed up with fact and some scaremongering it’s unclear which is which. It’s probably in our interest to take a few precautions with the bags of compost when opening. I’ll have a facemask handy now when I slice the bag open and then dampen it down with some water before mixing. I’ll also damp down the wire wool.

Apart from that, it’s business as usual and no more thoughts of a caravan in the wilderness.