Brugmansia very prone to pests and are generally delicate plants that require a lot of care to get beautiful.
Fertilizer and water
Firstly, the plant must have a lot of water; the cold species are somewhat smaller, but still daily. A large plant in full bloom may require more than 10 liters of water daily.
Hot angel trumpets are also very greedy for nutrients. Fertilizer several times a week is required to get beautiful leaves and flowers. The leaves turn yellow if no fertilizer is supplied, especially nitrogen (N). The easiest way to get enough nitrogen is at once or two a week to provide a full-bodied triple ammonium chloride. I only use the fertilizer that was cheapest when I last purchased, but you can go for an NPK with high N-numbers if you want to do the best for your plants.
A little warning, you might give hot English trumpets too much manure. Acute eutrophication appears on leaves, pointing directly up to the sky. This is usually harmless and corrects during a day of daylight. However, you can safely water the plant without underpots, and if it is particularly bad, change the soil.
Aphids are a particular nuisance that we must be able to relate to if we want to grow angelic trumpets. By temperature changes and changes in other climate conditions, such as after a long wet period, the plants are easily invaded. The lice are primarily on the back of the leaves, and especially the spikes with new leaves are very exposed. The way to get lost is insect soap. There is no reason to use poison. Mix only liquid brown soap (without additives, e.g., Coop), household spit, and water in the ratio of about 1: 1: 7. Bring the mixture into a spray bottle and spray the entire plant as it drives from it. Repeat the procedure every three days until the loops are gone. You can rinse the plant with water before spraying, so you get the most of the lice, and the treatment goes faster.
The reason for spraying every third day is that you catch most newly cut lice before they reach eggs.
If your treatment with the homemade insect soap does not work, it’s because you have not been thorough or persistent enough.
Another major nuisance is whiteflies, also called Mellus. The small white flies are treated in the same way as aphids.
The hardest, but also very common nuisance, is spider mites whose destruction is seen far earlier than it is possible to spell their spider. It is very clear that they are spider mites when the plant is spun into a fine spider spindle, but before then, you have already experienced brown plums on the leaves, juicy leaves hanging straight down (so you might have thought it was missing water). The attacks of the spider mites put the plant back to the degree that neither lice nor whiteflies can end up with. For the most part, the spider mites are not visible to the naked eye, but one can see the little animals. My experience is that significantly longer treatment with insect soap is needed to hit spider mites, but the treatment is the same as for lice and whiteflies.
Some are bothered by small flies, ie banana flies. Here it is usually about the earth being rotten and changing.
Weather and wind
You already know that angel trumpets should come in when the frost comes. In fact, before we reach below 8 degrees (a few species can handle slightly lower temperatures). If the plants get frost, they may sometimes survive well, so give your frostbite a chance to cut it down and wait for root shoots for up to a year.
Blown is hard at the flowers that turn brown and damaged and easily blow off. The leaves are a bit more resilient.
Sun is good, but the direct sun gives leaves with sunburns. It is seen as dry areas that become whitish.
The warmer it is, the shorter the time keeps the flowers. If the plants are optimal, you can experience the same flowers for months, while the summer heat can get rid of them in a matter of days.
Finally, I would like to point out that the leaves of angelic trumpets are often changed. It is, therefore, quite normal that there are falling leaves around your plant every day.