March is the time to prune your Camellia, as soon as the flowers fade. Remove any dead growth first, and then trim each stem back to a healthy outward facing bud to shape the plant and remove the faded blooms. Reduce the long stems at the top of the plant too. This should promote plenty of new growth, making the plant bushier and increasing the chances of more flowers next spring, as Camellias only flower on new growth.
After pruning provide a mulch of organic matter around the base of the plant, but don’t mound it up around the stem. Remember to keep your plant well watered throughout the summer using rain water instead of tap water (as the lime contained in tap water will reduce the acidity in the soil over time).
You can certainly prune out any damaged stem tips now and they will reshoot quite quickly at this time of year. This winter it might be worth throwing a couple of layers of fleece over the plant on particularly cold nights to give it a little more protection.