Narcissus, virus, compost

Max Withers
Wed, 14 Feb 2007 12:00:15 PST
I was intrigued by the range of responses this question elicited, so I 
did a little research. Relevant results from the most recent review I found:

> For 27 out of 32 pathogenic fungi, all six oomycetes, seven bacterial 
> pathogens and nine nematodes, and three out of nine plant viruses, a 
> peak temperature of 64–70°C and duration of 21 days were sufficient to 
> reduce numbers to below, or very close to, the detection limits of the 
> tests used.
> Several plant viruses were temperature-tolerant. These were CGMMV, 
> /Pepper mild mottle virus/, /Tobacco rattle virus/, ToMV and TMV. TMV 
> requires a peak compost temperature in excess of 68°C and a composting 
> period longer than 20 days for eradication. However, TMV is degraded 
> in compost over time, and can be eradicated after a composting period 
> of 26 weeks, even at low temperature (31°C). ToMV in infected seeds 
> can withstand over 70°C in an incubator for over 20 days. [TMV= 
> tobacco mosaic, TomMV= Tomato mosaic; 31 C= 87.8 F; 70 C = 158 F]
> It is clear that the detection limits in most studies were quite poor, 
> with infection levels of up to 5% likely to be undetected regularly
Noble and Roberts, "Eradication of plant pathogens and nematodes during 
composting: a review," Plant Pathology 53 (2004), 548–568.…

Since my compost undoubtedly already harbors a wide array of pathogens, 
I will probably add the narcissus and keep the result far from my 
important plants. I like Diane's suggestion of naturalizing best (though 
it wouldn't solve the disease problem), but I can't say I love the 

Thanks all,

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