Mark 6:46 (NKJV)
And when He had sent them away, He departed to the mountain to pray.
In this chapter, Jesus had just finished feeding the 5,000 with only two fishes and five loaves of bread. And He was about to walk out on the water to the disciples who were struggling with their boat in a storm. But Mark records that Jesus departed to the mountain to pray. Crowds had pressed in on Him all day, but He wanted to be alone with His Father in prayer. From the text we can know that he spent about ten hours in prayer on that mountain before going out to his disciples on the lake at about 3:00 AM.
Jesus was doing incredible miracles, demonstrating his power, but more importantly, demonstrating who He is. But in His humanity, he needed that connection with His Father. Not in short popcorn prayers but in long extended prayer, at night and on the mountain alone. If Jesus needed such time of prayer, how much more should we, if we need a miracle, spend concerted time in prayer alone with our Father in Heaven.
Matthew 6:6 (NKJV)
But you, when you pray, go into your room, and when you have shut your door, pray to your Father who is in the secret place; and your Father who sees in secret will reward you openly.