Brugmansias (broog-MAN-zee-ah) are famous for their large drooping flowers, which give the genus its nickname of angel’s trumpets.
These plants, now extinct in the wild, have become quite popular over the years.
While the 7 main species and 3 variants are a little harder to grow than the Angel Trumpet cultivars, they can be easy to care for overall.
But one common sticking point for many is choosing the right fertilizer for a brugmansia (or brug, for short).
Best Fertilizer for Brugmansia (Angel Trumpet)
A balanced liquid houseplant fertilizer is generally best.
However, switching to a different NPK ratio at the end of spring has its own benefits.
Advantages of Liquid Fertilizer
Liquid fertilizers are easy to apply, as they can be given as part of your watering routine.
They have a low risk of causing chemical burns and are easily absorbed.
Disadvantages of Slow-Release Fertilizer
Slow-release fertilizers are a popular way to supply nutrients. For many homeowners, they are not practical.
They don’t reduce the amount of work involved, as the liquid fertilizers are always added while watering the plant.
Granular fertilizers have a much higher risk of causing chemical burns to more sensitive plants.
Finally, the components in slow-release pellets don’t break down at the same rate, causing the plant to get different amounts of a given nutrient at different times.
If you wish to use a slow-release plant food for your garden plants, organic matter is the better solution.
Understanding NPK Ratios
Both slow-release and liquid fertilizers are graded by an NPK ratio.
This ratio is the percentage of nitrogen, phosphorus, and potassium present in the fertilizer.
- Nitrogen helps in a plant’s stem and foliage growth, but too much can hinder flowering in favor of foliage.
- Phosphorus is essential for heavy blooms, but too much can lead to a potassium deficiency in the plant.
- Potassium is vital to almost every aspect of a plant’s general health.
Picking the Best Ratio
A balanced fertilizer with a 20-20-20 NPK ratio is perfect for those who prefer to use a single fertilizer throughout the Brugmansia growing season.
However, it’s often a good idea to use two different fertilizers, resulting in the best results.
In spring, either use a balanced mix or one containing higher nitrogen levels to promote growth.
When summer arrives, switch to a fertilizer with higher phosphorus levels to encourage plenty of big, beautiful blooms.
Note that your choice of fertilizer blend should also include copper, iron, magnesium, and zinc to ensure optimum plant health.
When or How to Fertilize Brugmansia
Feeding should be done every 2 weeks in spring and summer.
Young plants should have their water-soluble fertilizer diluted by half.
Pro Grower Tip – A commercial Angel Trumpet grower shared the following:
When growing in pots Angel Trumpet plants are heavy feeders and heavy drinkers.
Best Times to Fertilize
Feed your brugmansia shrub every 2 weeks at the same time you water them.
This helps ensure the fertilizer is absorbed into the soil and reduces the risk of chemical burns.
When propagating a brugmansia, avoid feeding until the plant is a couple of months old.
That gives the roots time to establish themselves and helps reduce the risk of burns.
Do not feed the plant while it’s dormant in fall or winter, as doing so could harm or even kill the plant.
Note that organic compost is a type of natural fertilizer, so you should not use liquid fertilizer and compost together.
Organic compost should be applied approximately 1″ inch thick in spring and again in summer.
How to Fertilize Angel Trumpets
When feeding young plants, provide the fertilizer at ½ strength and stick to a balanced formula.
Remember, it will be 2 to 3 years before the plant blooms, so there’s no reason to increase the amount of phosphorus before then.
Once the plant is well-established, you can switch to full-strength doses.
During the summer months, you may wish to switch adult plants to an NPK of 7-9-5.
This change will encourage plenty of healthy blooms.
You may also wish to augment the fertilizer by mixing 1 tablespoon of Epsom salts per gallon of water once per month to provide more magnesium.
Just be sure to provide the Epsom salt mix during a watering between fertilizer doses, as providing both at once carries a high risk of burns.
Signs of Overfertilizing Brugmansia
Too much of a good thing can be harmful, and an excess of fertilizer can wreak havoc on your brugmansia.
Some common signs of overfeeding include:
- Brown margins and leaf tips
- Damaged roots
- Few or no blooms
- Leaf drop
- Reduced growth rate
- Yellowing of lower leaves
When this happens, you’ll need to flush the soil with a long, deep watering.
It may also be necessary to transplant a container specimen to a pot of fresh soil.
Be sure to prune away any heavily damaged leaves and branches.
After flushing out the soil, avoid giving the plant any fertilizer for one month so it has time to recover.