Wouldn't be such an important plot point if she didn't.

She touched the needle, and the fairies' gift rang true. She fell into a deep sleep, and so did the entire kingdom. The fairies knew that only true love's kiss would break the spell, so they left the castle to find the prince she had fallen for. While they were gone, Maleficent took over the castle, covering it with dark vines and thorns. As far as she was concerned, the kingdom would sleep forever! She would never let the prince kiss the princess!