In article ,
Baz wrote:

I wonder if a gardener can pick up and carry/transmit spores, disease or
parasites and such on their clothing or even on the bodyhair, and carry
them to the garden. Sort of cross contamination. The reason why I wonder
about this is because my vegetable garden is the only one I know of for
a mile or two, and I keep on getting different pests and diseases year
after year. This year it is the gooseberries, which have been here in
this garden for 40 years(so I am told) without any problems.
Then comes mildew 3 years ago and this year sawfly. I havn't been able
to grow any veg this year, but next year I know that there will be some
insect or infestation to burst my balloon.

They can, but that's not the usual reason. Blight overwinters on
a wide variety of garden plants and weeds, and is wind-borne.
The same applies to most pests.

However, the root cause of variation with blight, mildew, rust
etc. is the weather. They thrive under specific circumstances
and, without those, you don't see them. That doesn't stop them
being ubiquitous, which they are.


Regards,
Nick Maclaren.