You should make sure that your hair is at least ¼ of an inch (or as long as a grain of rice) before you get waxed. This takes a minimum of two weeks of hair growth. This will ensure that all of the hair can be removed. If you let you hair grow out properly before your wax, you can expect to be hair-free for a minimum of 1-2 weeks. You should expect two additional weeks of growing your hair to the length it needs to be to wax again. There are many factors that contribute to hair growth rates, including medication and hormones.