If you want to cover your fence FAST, the best choice would probably have to be Morning Glories.
Morning Glories are very fast growing plants, that depending on the species, may be annual or tender perennial vines with light green, heart shaped leaves.
They produce a non-stop show of large, blue, pink, purple, red, or white trumpet shaped,
sometimes fragrant flowers from early summer until the first hard frost.
Each flower only lasts for a single day or night.
The Moon Flower, Ipomoea alba is a night blooming species with fragrant white flowers.
Moon Flowers may also open on overcast days.
Morning Glory flowers will attract both hummingbirds and butterflies to your gardens.
They may die in the winter, but Morning Glories readily re-seed themselves each year,
and will rapidly cover your fence the next spring.
Warning: Morning Glories have an annoying habit of penetrating landscape weed-blocker fabric under inches of landscape bark.