I'm afraid some of the hoyas do drip a lot, I guess to attract their pollinators. Hoya kerrii I've heard is particularly bad. If yours is bad, I would suggest putting a tray under the plant the minute you discover it's flowering. I'm not sure what the best way of removing all that sticky sap is, perhaps other people will chime in. Of course one of the solutions would be to remove all the flowers, but that would mean you wouldn't be able to enjoy the flowers any more.
I don't know which your hoya is, but it may be a variety of carnosa - look it up on the web, it's the most common hoya available.
Hope that helps, Hills

Marcincon,

Carnosa sap is usually more watery than sticky, but I don't really have any trouble with it dripping off the plant like I do with kerrii. It usually stays on the flowers unless it gets disturbed. If your plant is in a high-traffic area and gets bumped, that might be the problem. But if you've got a particularly sappy one that drips without being disturbed, I would just lay some newspaper under it - that way, you can just take it up and put down new when it needs it. This is what I do with my kerrii. It's in my GH, but I get tired of cleaning up the super-sticky almost black sap off the tile floor. It cleans up with just soap and water, if you don't let it sit for a long time. A little bit of vinegar on a sponge takes it right up if it's a little more "set."

Congrats on your flowers!

Denise in Omaha

Hi I don't know about hoyas being sappy, but I do know that scale is very sappy you said your plant was sticky and sappy before the flowers were on..scale looks like little brown bumps under the leaves and vines, it draws the sap out of the plant and that is why it is so sticky everywhere and are very hard to get rid of, I just found it on one of my plants I sprayed it every day and scaped off the scale, I finely though the plant away, I didn't want the rest of my plants to get it..I had it once before on a plant and the plant died before I got rid of it..maybe someone here knows a good way to get rid of it...any way I would look for the scale, it is very sappy and sticky and messy to clean up.
I hope it isn't scale...just thought I suggest to look for scale...bye linda

Best way to get rid of scale is a dystemic bug killer ( lots on mkt) only ghing that works, i watered it into the compost!