I have a camillia that seems to have sooty mould fungus. I have sprayed neem oil 2 times in the last month and sprayed with soapy water. I see little black spots on the new leaves though, as if its happening again. Should I be spraying neem oil every week? and if so, for how long? This disease did not affect the flowers as they were magnificent.
Anne Arundel County Maryland
Hi - We see the sooty mold on your plant, which is a sign that there is a soft scale infestation. Please take a look at our information on cottony camellia scale and how to manage it. https://extension.umd.edu/hgic/topics/cottony-camellia-scale-shrubs
For this type of scale, you can treat your plants this month with horticultural oil to help smother the more vulnerable juvenile insects when they first hatch (called "crawlers") and use a slightly more concentrated "dormant oil" to manage overwintering scale in the dormant season (when leaves have fallen from deciduous trees). Thorough coverage of all plant surfaces, including undersides of the leaves, is important for effectiveness.
Since this is a very large shrub, spraying may be difficult or impractical. You may want to hire a landscape professional to apply a treatment for you. A landscape professional would have access to other types of (stronger) insecticide products and equipment to treat a shrub of this size more effectively.