Many of its leaves, especially on the lower part of the plant, are turning yellow, wilting, and drying up. What am I doing wrong?
I Have a Brugmansia in a Pot on My Deck
Certified GKH Gardening Expert
Yellowing leaves is generally a watering issue.
Brugmansia need plenty of water. Twice a day watering may be needed as the warmer summer temperatures rise.
Make sure the pot is well draining.
Here is a great article with care requirements.