He said 9 hours of direct sunlight. Meaning that the sun is hitting the marijuana plant for 9 hours without any obstacles in the way of the sun creating shade on the plant. A marijuana plant will still grow great with 5-6 hours of direct sunlight. Its harder in determining direct sunlight in the winter with all the leaves off the trees, the sun is in a lower spot in the sky during winter, and the days slowly get longer every day in spring until june 21st, the longest day of the year. If you are actually getting 9 hours of DIRECT sunlight, that will be fine, if there was not enough sunlight penetrating through branches, then it would be time to do a little clearing of branches, small trees etc. Hope that helps, happy toking