Add a soil wetting agent or add a wetting agent to a watering can and water in well. If your rhododendron or camellia is unwell dig it up carefully, put it aside, and hose off a little soil. Add at least 70 litres of organic matter, dig in well and replace into its former site at existing level of the rootball, water in well with added wetting agent. When selecting a camellia or rhododendron make sure the variety suits the position, this will avoid disappointment. They add a different dimension to the garden in their form and early flowering habits.
Many varieties can take more exposure than japonicas.
Now is the time to fertilize. Mulch when finished. On good healthy green plants a mulch is all that is needed. Don't use chicken manure fertilizers on rhododendrons or azaleas . Camellias will take chicken manure fertilizers, but go easy.