Answer: Camellias and gardenias are acid-loving plants and prefer an acidifying fertilizer. You will find several products on the market with names like "azalea and camellia food" or if you want a natural product, you can use cottonseed meal. Cottonseed meal will give a slow release of nutrients as it breaks down. It should be worked into the soil surface or covered with a mulch of pine needles.
Hydrangeas can be fertilized with the above products or a standard turf fertilizer. If you make their soil more acid their blooms will become blue. If their soil is a higher pH (more alkaline) their blooms will be pink. Your choice!
It is best to fertilize the plants in small amounts, about 1/4 cup per bush (1/2 cup for cottonseed meal), every 3 or 4 weeks from spring to mid summer. However, the most important time is in late spring to early summer.
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