No, but if you go to your own profile (click your avatar), then go to the Questions tab, there is an option to “Hide on profile” for each of the questions you asked. This doesn’t remove the question from Fluther – meaning that people can find it if they scroll down in the appropriate section or if they Google the question. But at least they won’t be able to go to your profile to figure out what question you’re talking about now, or see it if they go to check out your profile after reading your comments on other questions.
The first method (scrolling by date) for encountering questions is key in the day or two after it has been asked. The latter two will occur throughout your time on Fluther.