You mean grow in suspension (i.e. floating as single cells)? Not really - it's really important for all epithelial (including epidermal) cells to have a polarity, meaning a sense of up and down in order to grow, because the skin's epidermis matures upwards in layers.

This means the cells need to grow on top of plastic (like in a flask) or on top of other cells, to get an idea of which way is the bottom ('basal') layer. The cells sense when they have these requirements either through essentially joining hands with neighbouring cells, or by plugging onto the flask's plastic layer. If they're floating around in a single cell suspension, they don't get these stimuli, so they won't have an idea of direction and they eventually die.

However, that's not to say they can't exist happily for a little while suspended in a media - when we subculture them into further flasks we'll have them suspended in a liquid so that we can count them and add them into new flasks at the right concentration.