A beautiful tropical shrub that can attain a size that is tree-like, the angel trumpet (Brugmansia spp.) is a fast-growing plant renowned for its trumpet-like flowers that release fragrance at night. Tender to cold, the angel trumpet will suffer leaf and branch die-back when temperatures flirt with the freezing mark, eventually being killed outright if prolonged subfreezing cold also penetrates the soil around the roots. Tip pruning is easily done when the plant is actively growing, and strategic removal of branches can improve the structure of the plant and increase flowering and resistance to storm winds.
Allow the angel trumpet to grow upright until the stem or trunk naturally branches, forming a 'Y'. Avoid pruning new growth that is soft and green in color.
Remove any competing suckers, or leggy new growth stems, from the base of the plant as desired. Removal of suckers focuses the plant's energy on the selected desired stems already growing. If a multi-trunked angel trumpet is desired, select two or three suckers to grow from the base, but give them space so they do not grow into each other.
Tip prune any dead or soft, rotting stems during the growing season. Make the pruning cut with the hand pruners back into firmer, healthy stem tissue. The cut can be made anywhere on the beige stem growth, as an angel trumpet will form new grow buds from many locations on its stem after a pruning.
Select the new growth to retain on stems after pruning. The results from pruning vary. Sometimes there is die-back; other times, a massive sprouting of new stems. Pinch or cut away new growth as desired to train branches to grow in locations where you wish to create an impressively-shaped plant.
Prune after a flush of flowers. In regions with year-round warmth and no frosts, the bloom cycle of the angel trumpet follows the lunar phases. Maximize the flowering by pruning branches after flowering so new growth can quickly grow back and flush new blossoms a month later.
Severely cut back stems that are overly lopsided, bending or becoming damaged from a thunderstorm event. Make a crisp, one-motion cut across the stem at an appropriate height to remove the branches or stem. Use loppers on large stems to make a clean cut. Consider chopping away upper branches to lessen the weight on the trunk that is to be removed.
Avoid painting the pruning wounds on the angel trumpet. Allow the plant to naturally air dry and callous the wounds. If there is a threat of stem rot and fungus, sprinkle the stem wounds with cinnamon or anti-fungal powder after the wounds have calloused and dried.