Look at the undersides of the foliage. If you see whitish spots, you're likely looking at male tea scale. These males will secrete a white, woolylike mass. Females are dark brown. Oil emulsion sprays will help control outbreaks.
Camellias require a highly organic and slightly acidic soil.
Good drainage is a must. November to March is the ideal time to plant camellias. A well-draining spot that receives morning sun and some filtered shade is ideal. Do not plant too deep. As much as half of the root mass should be above ground level.