Dwarf baby tear question!!?

ok so i got a 2 week cycled tank got water tested, its all good, im going to add my first plant to my tank and that plant is dwarf baby tears. i want to make a carpet on the gravel and the guy said for the plant to grow i have to take out my filter and put plastic over my tank so that they can grow? he said it would create moisture something like that do i listen to him or what should i do?