Tiny bugs infesting my gardenias

It sucks! Every day, I get my spray bottle and wash away these tiny green and brown bugs that infest the leaves of my three gardenias. They've plagued one plant, especially, and are working on a younger one. I wash them away, wondering how I can get rid of them. I don't mind the high-maintenance work, but tonight I stumbled across a site that explains how ladybugs can be natural killers of aphids.

I don't know if these tiny bugs are aphids, but there was a nice little black ladybug (above) on one of the gardenias today. It was running around like it was a little lost. I never saw her before and she may have just been lost. I live in an apartment building pretty high up, so the chances of more ladybugs landing up here are remote. I'm glad I didn't get rid of it. I hope she sticks around and eats ALL the aphids and other little pests.