Angel trumpet, or Brugmansia suaveolens, is an exotic-looking plant featuring large blooms around 12 inches long that resemble trumpets. Best success rate for me is to take runners from the plant and replant in same area next to trumpet vine. It helps that there are many ways it can be propagated including from seeds, cuttings, division of roots, suckers or layering. Trumpet vines easily propagate, often even without any input on your part. Trumpet Vine Plant Propagation. The ideal cutting size is 8 to 12 inches in length. Propagating Angel Trumpet is the quickest way to get new plants and it is relatively easy to do. When the seed pods on your trumpet vine turn brown and split open, you can harvest the seeds and sow them in spring. The blossoms open at night, release a strong, sweet aroma and close again with the morning sun. Mark the top of the cutting with a permanent marker so that you know which end is the top. Sometimes the plant can be divided in early spring or late winter when it's dormant. Propagating Angel Trumpet. Sometimes when propagating it just takes lots of cuttings and more practice. Or dig up side shoots from the mother plant .