Title: To work it and take care of it
God never intended for man to be busy as we are today. Indeed not even to plant a garden, but to take care of it, since the garden was already in existence. He was to be a gardener, enjoy his work, and have plenty of time on a daily basis to fellowship with his Creator.
And even in the whole design of creation, the gardening takes second place, because the real purpose for life is the worship of God. Again on a daily basis.