Multi purpose to ericaceous
Last year I planted two camellias in multi purpose in pots and realise it should have been ericaceous. How do I change it please? One has produced lots of blooms the other only one.
Multi-purpose is likely to be slightly acidic due to the peat moss. Does the bag give the pH of the contents? If not, look on the companies website. There are several products, like slow-release sulfur, that lower pH but you won't know how much to use without first knowing the present pH. You might also use a fertilizer designed for acid-loving plants. It is intended to lower pH and feed plants being grown in neutral to alkaline soil. The following article discusses lowering pH. https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/raise-acid-level-soil.htm