Colchique d'automne is the name of the plant called naked lady in English. It's not an accurate translation of naked lady as a woman without clothes on.
Added after reading Keith's post: He's right, without a context, there's no way to know if you're opposed to drawing flowers (first suggestion) or women (second suggestion) .
exactly. It is an exercise we have been given to do (as silly as it seems) and this is one of the sentences Bart Simpson writes on a black board for a punishment. I have never come to translate "naked ladies" so thought I would get the most informal way to say it here on word reference. Thanks to all who have replied.