Brugmansias (broog-MAN-zee-ah) are gorgeous flowering plants that produce blooms of 6″ to over 14” inches long, giving them the common name of angel’s trumpet.
These Brugmansia plants are now extinct in the wild but continue to thrive in gardens worldwide.
While not especially difficult to care for, the topic of pruning seems to have as many answers as there are people to ask.
Here’s the lowdown on what you need to know (including the reasoning behind various practices) when pruning your Brugmansia.
How and When to Prune Brugmansia Angel Trumpets
Pruning a Brugmansia is relatively easy and best done in the fall.
The only important detail is to always cut above the “Y” if you want the plant to flower next spring.
Is Pruning Even Necessary?
Unlike most plants, Brugmansia generally doesn’t need to be pruned unless you want to maintain a particular shape.
In regions with frost risk, it may also be prudent to cut the plant back before winter sets in.
Brugmansias are incredibly toxic in every part, and consuming even a tiny bit of tea from the flowers can cause violent hallucinations or even death.
Keep yourself safe by wearing gloves and goggles when working with an angel trumpet, and be sure to wash thoroughly afterward.
Likewise, protect your plant by using only sharp, sterile shears and resterilizing after every cut.
Best Time to Prune
By far, the best time to prune a Brugmansia is in the fall.
Many growers prefer to wait for the first mild frost, which causes dieback.
However, others believe the plant fares better if pruned prior to the first frost, so it has no open wounds.
In warmer climates that get only mild or no frost, it’s not uncommon to prune the plant back in spring after the threat of cold weather has subsided.
One of the biggest arguments for only pruning in the fall is the fact that these plants can be early bloomers.
By pruning them in spring, you run the risk of cutting away the beginnings of new blooms.
This is especially true in zone 12, where a Brugmansia may bloom all year long under the right conditions.
Identifying the Y
The most critical aspect of pruning is to identify the “Y”. Unlike normal branching, the Y is where new growth springs up, and Brugmansias will only develop flowers at these junctions.
When possible, prune above these Y branchings, leaving 6 to 10 nodes.
You can also cut below the Y, but this will cause the already slow-growing angel’s trumpet to take a year of growing before it can produce more blooms.
Shrub or Tree?
The most common reason people want to prune an angel trumpet is for shape.
Angel’s trumpet can grow in either a shrub or tree form, depending on how you prune it.
You can expose the central trunk for a tree-like shape by removing the lower growth.
Conversely, it will look more like a shrub if you leave the lower growth.
This includes suckers and new stems, which spring up around the main trunk.
While these suckers draw some energy away from the central plant, they can give your angel trumpet more of a round habit.
Old Growth vs. New Growth
One of the little quirks about a Brugmansia is that it will only bloom on new growth.
This means you’ll want to prune back this year’s growth to the older, woody Y sections.
New growth is green and supple, while the older growth has a woodier firmness and beige to brown coloration.
Cutting Back to Overwinter
This can be an iffy venture unless you know whether your Brugmansia is from the warm group or cold group.
Cold group plants have a slightly better tolerance to frost and can survive outdoors in zone 9b, while warm group plants need to be in at least zone 10b.
A prevalent practice is to keep an angel’s trumpet potted so it may be overwintered indoors.
Before bringing it inside, cut the entire plant back by ⅔ of its size.
Because there’s an increased risk of cold damage if the plant has been freshly pruned, growers in warmer climates may simply leave the tree to die back.
Come spring, they cut the plant back by ⅔ once the threat of a light frost has passed.
In regions where there’s a risk of frost, another common practice is to severely cut back the brug, then cover the roots with a heavy layer of organic mulch or compost.
The plant may still suffer some dieback, but the roots will be able to regrow from the base.
Finally, in zone 12 (and some parts of zone 11), your angel trumpet may bloom all year long.
To help promote continued blooms, you can prune back the tips while deadheading.
This practice can lead to new blooms in about 4 to 6 weeks.
Pruning for Health
Finally, there’s the topic of pruning an angel’s trumpet to maintain a healthy appearance.
Cut back damaged or diseased branches to the healthy tissue when you see them.
Not only does this look better, but it can also help prevent the rest of the plant from becoming ill.