Although new hair growth generally refers to hair that has recently grown, in the context of straightening, it refers to hair that has grown since you last permed or relaxed your hair. Most people notice new hair growth a month or more after using a perm or relaxer. Because the new hair growth in its natural state (unpermed and unrelaxed), straightening it gives it the same appearance as the rest of your hair. Depending on its length, there is a variety of ways to straighten new hair growth.
Apply another perm or relaxer to the new hair growth, provided it is at least one inch long, to straighten it. Split your hair into four sections and apply the perm or relaxer from the roots to where the new hair growth ends. Avoid applying the chemicals on hair that is already straight to prevent hair breakage or over-processing.
Straighten new hair growth using a traditional or electric hot pressing comb that has been heated until it is moderately hot. Spray clean dry hair with a heat protectant spray, then run the hot pressing comb through the new hair growth. Be cautious near the scalp, hairline and ears.
Blow-dry your new hair growth to straighten it. Spray wet hair with a heat protectant spray, then run a blow dryer with a comb attachment through the new hair growth until it is thoroughly straight. Work with one-inch thick sections using a 1500- to 1800-watt blow dryer.
Straighten new hair growth using a high quality ceramic flat iron that has been heated for about 15 minutes. Spray clean dry hair with a heat protectant spray, then run the flat iron along the new hair growth, in small sections, until it is thoroughly straight. Be cautious near the scalp, hairline and ears.