Answer: The sweet autumn clematis would look lovely on a pergola and blooms in the fall with fragrant, fresh white blossoms. It will do best in a good rich soil that is moist yet well drained; plant it on the north side, for example, so that its roots are shaded during the day by the pergola. This perennial vine will do best planted in the ground. For containers such as half barrels, you might consider morning glories or moonflower vines or similar annual vines for all season blooms. These will not be large enough to cover your pergola roof, however.
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