Mulching is very important for camellia health. The material should be placed from about four to six inches from the base of the plant, to as far out as the branches extend. Spreading the surface around the camellias with two to four inches of pine straw, leaves, shredded bark, or other organic matter (but not peat moss) will help eliminate weeds, retain moisture and moderate soil temperature. Do not pile mulch too high, as this can keep the soil too wet and provide good conditions for root rot. Do not pile mulch too close to the base of the plant.
Camellias prefer moist, but not soggy, soil at all times. Water until the soil is wet to a depth of 14" to 18." Be aware of how much moisture the soil is getting from rain and/or sprinklers, so that the camellias do not get waterlogged. If they do, this can result in problems which may result in death of the plant. (See Diseases: Prevention and Treatment.) A general rule for watering is, "If in doubt, don't."
There are many recipes for camellia food, and different ideas as to when to apply it. Camellias should definitely be fertilized in the spring following flowering. They may benefit from a feeding earlier, just as the buds form, to give strength to the blooms. Some growers insist that cottonseed meal alone is enough to keep camellias blooming year after year. It is organic, slow release, and does not burn the plants.
Another excellent natural fertilizer is manure. Horse owners and those who board horses may be delighted to have some of the horses’ extra excrement hauled away. Take the aged manure; if it is fresh, it will burn the camellia roots.
If you prefer quicker action, commercial fertilizers especially for camellias are available. If you have the time and patience, you can concoct your own mixture. Information for doing this is available from a number of sources. Remember that organic fertilizers are safer but slower to show results; commercial ones act faster but have the potential to damage plants by burning leaves and roots. Start with a soil test to find out your soil's particular needs. Camellias prefer a soil pH of 5.5 to 6.5. Your local agricultural extension agent should be able to help you with the soil test.
Camellias require very little pruning except for the removal of damaged branches and long shoots that detract from the attractive form of the shrub. If it should be necessary to cut back severely (no leaves left), it can be done safely from Valentine's Day to around the first of May. Cutting out the dead, weak, or diseased stems can be done anytime.