Camellias like partial shade. Too much sun can scald the leaves, turning them yellow. Test your soil in that location. They love well-drained, slightly acidic soil with a pH of 6.0 to 6.5. Once you do the test, you'll know how to adjust. Mixing 50% of a camellia planting mix with your native soil is a great way to bring it up to par.
Dig a hole at least 2 feet wider than the root ball, leaving a column of soil in the middle untouched. This column is very important. Your root ball will sit on top of this and it will prevent it from settling down too low. Dig a moat around your column to backfill later but make sure that the soil in the column isn't disturbed. If you dig the entire hole out and backfill to create the column, it won't be sturdy enough to keep the plant from settling.
Place the camellia's root ball on top of the column and backfill around the plant. Use your 50:50 blend of camellia planting mix with the native soil, or the soil alone if it's a perfect match. When you're through backfilling, the top of the root ball should sit just above the soil so the shallow roots can get some air.
Create a berm around the plant and add mulch. A berm is a mounded ring of soil around the plant that will hold the water in so it can get to the plant's roots. The mulch will also help to retain water. Pine straw and pine bark are two great options for camellias but don't pile it higher than 4 inches. Camellias like to stay moist but they don't want to be soggy.
Two common problems with camellias: First, blooms fall off. Fallen blooms could mean your plant was either too wet or too dry. This also happens if you have an extreme temperature spike or an infestation of camellia bud mites. If you have the infestation, you can control it with a miticide. Second, brown spots appear on the flower petals. Camellia flower blight could be the cause of brown spots on the flowers. There's no cure for this disease but you can control it. Collect all the flowers with brown petals and destroy them as soon as they fall so the disease can't spread.