Hi Bill
I know it's notjing to do with what this forum is about but I do like you
question. It's good to know there are places on the web where you can ask
that sort of question (made me smile).
I looked on the Kew site (The Royal Botanical Gardens). As you can tell -
it's my coffee break.
http://www.kew.org/
Anyway I looked on there site and they say although marigolds do spider
mites there is a trade off with the fact that they also attract beneficial
insects such as hoverflies and ladybirds (both of which feed on aphids) so
you may still want o some cultivate just a few.
Oh well back to access