Although it is largely unnecessary to prune your camellia plant, it can be beneficial in some areas. Pruning this particular plant can discourage the development of certain diseases and pests and can help shape the plant in the manner you desire. As with most plants, timing is everything but fortunately, camellias differ from other plants in regards to the repercussions of poor timing. You should always prune after the flower has stopped blooming. This goes for any form of pruning, whether it is disease prevention or reshaping. By waiting until the flower has stopped blooming, it will prevent you from accidently removing any flower buds. If you prune too early, it is not detrimental to your plant. It simply means that you may have affected the amount of blooms you will get in the following year and will have to curb your pruning enthusiasm the next time around.
If you are pruning to maintain the health of your plant and to discourage the development of diseases, simply snip away at some of the inner branches and leaves to allow for better airflow and light penetration. Camellia flowers are susceptible to aphids, mites, thrips, sooty mould, leaf gall, and a few others. With preventative action, the likelihood of these occurring will be significantly decreased. When pruning, use clean, sharp pruning shears and cut at the exact point where the small branch meets the main branch.
By pruning in a certain way, you can manipulate the growth and shape of your plant. To prune the plant's size, simply snip away at the branches that do not fit into the mental picture you have created for your plant. It is better to take a natural approach when trimming your plants rather than a formal square shape. To encourage them to grow larger next season, only trim an inch from the ends. This will cause your plant to create large foliage and blooms.