Q: Can you please help me with my angel trumpet? My plant is 3 to 4 years old, but has never bloomed.
It seems to have some sort of leaf infection. I have sprayed it with two types of flower and vegetable insect spray to no avail.
The plant is wintered in my garage. It's supposed to be big and full, covered with flowers in spring and summer. But it's never come anywhere like the photo from the plant catalog.
Also, is it supposed to be pruned in the fall? And what kind of plant food should I use?
Frances Williams, Sacramento
A: To more accurately diagnose the leaf problem or pest, bring a sample to the UC Cooperative extension office when master gardeners are available. Call (916) 875-6913 for hours. Or bring a leaf to the master gardeners' upcoming open garden day Feb. 25 at the Fair Oaks Horticulture Center in Fair Oaks Park.
If you notice that your angel trumpet (Brugmansia) has spots on its leaves, it may have a fungal infection, according to UC Master Gardener Bill Pierce. These "leaf spot" diseases can be caused by a variety of fungi and may cause the leaves to develop ever- widening spots in yellow, brown or purple, or may actually cause the tissue of the leaves to rot away.
Most leaf spot diseases are largely cosmetic, but they can weaken the plant and cause defoliation if you do not keep the infection in check.
Brugmansia are particularly susceptible to whiteflies and spider mites. These tiny insects can be spotted crawling on the undersides of leaves and often cause the plant to appear wilted, even when it's getting plenty of water.
Spider mites leave small, webbed residues in the crooks of leaves and branches.
Aphids and mealybugs may also present problems and may be identified because of wilting or because of the mold and mildew infections that often follow these honeydew-secreting insects.
Pruning the tree once a season (usually in fall after flowering) will help prevent the formation of a dense, humid environment that fosters molds and mildew. Cleaning leaf debris from underneath the plant will help prevent fungal infections like leaf spot diseases.
You can keep most insects at bay with neem oil or an insecticidal soap. Plain liquid dish soap diluted with water and sprayed on the tops and bottoms of all leaves on your brugmansia will make it unpalatable to most insect pests.
If your angel trumpet is already showing signs of infection, remove all infected foliage. Dispose of that plant material in a sealed plastic bag rather than dropping on the ground. Rake away all plant debris from underneath the plant and dispose of it in a sealed bag, too. (That will help prevent the infection's spread.)
If mites or other insects are creating problems, remove any moldy foliage and spray the entire plant with diluted dish soap or an insecticide. Monitor your brugmansia for signs of reinfection.
Consider using a slow-release fertilizer that contains a balance of nitrogen, phosphorus and potassium and other minerals.
Questions are answered by master gardeners at the UC Cooperative Extension services in Sacramento and Placer counties.
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