Phygelius plants susceptible to fungal diseases, viral infections
QMy red Phygelius has developed dark, purplish nodules on the stems, and new growth is contorted and doesn't open out. Is there something I can do to treat them or are they a lost cause?
— Jane Haley,
Morgan Hill
APhygelius, also known as Cape fuchsia or Cape figwort, is a relatively easy plant to grow and a great one to have in the garden for attracting pollinators. It can be susceptible to a variety of fungal diseases, viral infections and insect infestations.
The most common diseases are rust, verticillium wilt and root rot, all caused or exasperated by too much water, or overspray.
In the case of your fuchsias, I think insects are to blame. You might have thrips or fuchsia gall mites. Both of these insects are so small we can't easily see them and so we diagnose mainly by symptoms and damage. The gall mites are so tiny you really need to put the plant under magnification to see them; the thrips are less than 1/20th of an inch long.
According to the UC Integrated Pest Management website, ipm.ucanr.edu, the mites “live and reproduce within the folds of galled tissue and among plant hairs. As infested plants grow, some mites leave the galls and move upward to attack new terminal growth and blossoms. The mites occur on growing tips year-round and in flowers whenever present. The mite prefers cool growing conditions and its abundance and reproduction are reduced by warm temperatures.”
On the other hand, thrips can stunt plant growth and damage leaves. The tips of plants can become distorted and discolored, and take on a rolled appearance. The insects prefer the more succulent new growth portions of plants, but will eventually spread out to sup on older plant material.
Once either of these insects have gotten a good toehold in the plant, they are difficult to get rid of, but control is important because they will spread to other plants. Most gardeners recommend removing the infested plant entirely to prevent the insects from spreading to other parts of your garden.
If only a small portion of the Phygelius seems infected, prune off the damaged parts, bag them and put them in the trash. Do not add them to your compost pile. Immediately after doing this, change clothes, clean your shoes, wash your hands and use alcohol to clean your tools to prevent inadvertently carrying the thrips or mites to other parts of your garden.
You can then spray the pruned plants with a horticulture oil or insecticidal soap every two to three weeks.
If more than 50 percent of the plant seems affected, you're better off pulling it out completely.