Hi Zack! What type of Hoya do you have? And we would love to see a picture if possible. But I'm afraid different Hoyas have different length of bloom times. I'm not aware of anything that "may" keep them longer. I wish I did!
Good luck in the Fair and I would enter it whether still in bloom or not :).

This post was edited by teisa on Sun, Sep 15, 13 at 0:43

Flowering plants have to be in bloom or it can't be entered at the fair. It has green leaves with silver flecks in it. I never knew the name. The flower looks just like the one on the home page here. Not sure if all the flowers look the same or not?

The flower on the home page is the Hoya Carnosa. They are very pretty:)

I hope it works out, and stays in bloom for ya. Let us know.