I always add a fertilizer to camellias in Spring, in the form of 1/2 to 1 cup of cottonseed meal.I also add weak fertilizers like liquid seaweed, liquid fish or coffee grounds during the growing season. Coffee grounds -after they have been used to make coffee- do not contain enough acidity to acidify the soil but, I use them anyways to add some nutrients. You can also use composted manure, organic compost, or a general purpose, slow-release, chemical fertilizers with a NPK Ratio of around 10-10-10.

Since my soil is alkaline, I also amend the soil (to acidify it) with whatever I happen to have: garden Sulphur, iron sulphate, greensand, iron chelated liquid amendments, etc.I also add more mulch if needed.

You can just about add coffee grounds, seaweed and liquid fish whenever you want but I stop adding those in the Fall & slow-release ones in July-ish so the plants will go dormant before frosts arrive. After Spring, I will apply fertilizers again in May & July (if it is not hot) and I add a special fertilizer in September-ish. At around that time, I switch to fertilizers that are very low in nitrogen and add one last application in September or October. Nothing else after that until Spring.

Potted shrubs will need more frequent applications; the above suggestions are for camellias planted in the ground.

Here is more information:

https://www.americancamellias.com/care-culture-resources/general-culture-requirements/camellia-fertilization

I live near Nuccio's Nursery in Altadena CA, the growers that created Nuccio's Gem and hundreds of other cultivars. They use cottonseed meal for camellia fertilizer and recommend it to their customers.

Ah I'd love to tour their nursery! I bet it's beautiful!!!

Me too. It would be nice to be there when the early and late camellias are blooming so you can really "see" them.

I am so sad that I spent a whole week in the LA area several years ago and did not think of going to the nursery. Oh well. I don't think I knew Altadena was there or something.

It's a great place if you like camellias and they are very nice people. In bloom season they pick the flowers and put them in water in a display so you can see the blooms.