Dear David,

Thank you for contacting us about Distinctus riversii, a variety of trumpet vine. While not officially considered invasive in Oregon, the plant can be overly aggressive and usually requires pruning several times a year. With proper winter mulching, it may overwinter successfully but may not be evergreen in our region. This vine blooms on new growth, so it should be cut back hard in early spring to make space for fresh flowers. Care must be taken to avoid introducing it to uncultivated areas.

Evergreen alternatives are the Clematis cirrhosa and Clematis armandii. Both grow vigorously and bloom on new wood, so they too benefit from being cut back hard once a year.  Another evergreen clematis 'Avalanche' (Clematis x cartmanii 'Blaaval') is somewhat less aggressive but may be more difficult to find. I am not personally familiar with this cultivar, but it reportedly blooms on one-year-old wood and may be pruned in spring after blooming. 

Native deciduous vines include Woodbine (Parthenocissus vitacea) and Virginia creeper (Parthenocissus cinquefolia). They produce good fall color but do not have significant blooms. Again, these can be aggressive growers that require pruning to control them.

A hardy Oregon native is Orange honeysuckle (Lonicera cilios, ). While the plant is deciduous, the bright orange flowers are a magnet for hummingbirds from May to July. 

Please avoid planting English ivy  (Hedera helix) which is invasive and problematic in Oregon. 

I hope this information helps you. Please write again if you have more questions.