Answer: Alonsoas are tender, evergreen perennials that are usually grown as annuals. They can grow 9-24 inches high and have erect, branching growth. Their stems are wiry and they produce small, flat, 2-lipped blooms in the summer and fall. They can be grown outdoors during the summer, but other times they must be kept in a greenhouse having a minimum temperature of 45-50 degrees. They are natives to Peru and other parts of South America. Without seeing the damage I can't really offer a solution. Check carefully to see if you can find insects feeding or fungal spores or dots. Or you might just want to clip off the damage and wait for healthy new growth to appear. Mites like dry dusty places in which to live. Periodically hosing the plant off will discourage them. I can't really diagnose the problem with your nemesia without having more details about where it is growing and what care it has received. The symptoms might indicate over or under watering, sunscald or even a disease.
Good luck with your garden.
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