Which natural remedy exist against aphids?

[okieOrchid]

I was able to completely eliminate spider mite from my collection using this simple solution : put a couple of drops of Eucalyptic oil into the potting medium.
I repeat this application anout once a month and have NOT seen even 1 mites on any of my 100+ orchids

[sii]

I haven't seen any aphids around here.

But one day i went out to a nursery to check out some 'other' plants. While I was there we watched one of the ladies put ladybugs all over some rose bushes. They are considered a good natural enemy.

Don't know how this translates to orchids, but thought I'd share.