The tea tree oil will not dry up but the water will. The included DIY link indicates you might want to start with a heavier concentration of the tee tree oil, even one hundred percent with no water for an infestation. Once you have laid down the scent barrier, spraying the room every week with a lighter concentration will keep the centipedes away.

http://www.stepintomygreenworld.com/heal...

In my last question I described my situation with house Cintipedes in my dry room and it has become bothersome. Today a friend of mine gave me Tea Tree Oil and I put it in a spray bottle with water. It's musky strong on my nose, so I hope it'll be stronger on the Cintipedes. I sprayed out around my room, corners, Windows, and my door. I wanted to know if this would be a successful repellant overall? temporarily of course. When the oil dries up does that mean it will no longer effect the Cintipedes?