Answer: Trumpet vines are very large and vigorous, far more so than most clematis, and can even be nearly invasive if left unchecked. Clematis on the other hand are generally far less rambunctious. Roots are usually in proportion to the top of a plant, so for a smaller area simply select a clematis with a smaller mature size. Some reach 30 feet, others reach about ten. Nearly all clematis should do well in your area, so select one in a color you like and a size that fits your trellis.
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