I stated for the dress code to be 'tidy & professional' but didn't specifically put in writing 'black & white' clothing.
Hey honey
This sentence says all you need to know- ripped jeans etc is not imho deemed to be tidy and professional, nor would i think it be in most peoples if im honest.
Agreed if shes good at her job she could wear a bin bag and still be good. However her written contract states tidy and professional. As for black and white? As shes self employed i do think you would have a problem enforcing this. Remembering also that her business is also her business. However you can enforce professional and tidy.
Speak to her lovey and see how it goes.
Love n hugs xxx