Why do my palms, pointsettas and ficus have sticky sap all over the them?

Question:Its all over my floor and anything else near or under them even the wall. I know aphids and mealy bugs have battled both. I have looked closely and see nothing.. no crawlies, plus after I put them outside it stopped. I live in a seasonal climate, it snows in the winter so I cant leave them out

Answers:
M C
My first thought would be aphids also. The next thing could be damage to the plants, i.e. ripped off limbs, fronds, etc where the would would be dripping. If there are no oozing points and no aphids, then perhaps something is visiting. Try washing the plants with mild soapy water, rinse, and then cover with muslin gauze for a while.