I dye my hair red but my hair is starting to get dry.?

I know it's difficult keeping the red color without many trips to the salon every 4 weeks. I really enjoy having my hair this color, at least for this summer. Are there any hair treatments that anyone could recommend me that I can use for my dry ends? I have no frizz and my hair is not dull at all, Im just having a problem with my ends. I used Matrix shampoo and conditioner for chemically treated hair. Thank you :)