An epsom salt solution spray is quick & inexpensive.

'When diluted with water, Epsom salt is easily taken up by plants, especially when applied as a foliar spray. Most plants can be misted with a solution of 2 tablespoons of Epsom salt per gallon of water once a month. For more frequent watering, every other week, cut this back to 1 tablespoon.'

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/epsom-salt-gardening.htm

Many thanks Bathgate I will certainly give that a go.

I've never used Epsom salts as a foliar feed, just watered it into the ground. You can buy specific feeds for Camellias and Rhododendrons don't know if they are foliar or root absorbed as not used them.

it all the leaves Phloxie or just the odd one? the odd one will be shed as it has outlived its active life and is quite normal.

I always mulch generously with fallen pine needles from a cedar tree, they love it and given time they will really improve the soil and the camellia, you can also use some of those ericacious slow release fertiliser, miracle grow do some and they are excellent they are similar to those osmocote granuals,all the acid lovers will benefit from these methods.

The foliar spray is directly applied and absorbed through the leaves to impart almost immediate results. It works.

Water Sequestrene Iron solution around the base - it will be taken up very quickly by the camellia, IF its chlorotic because of manganese or iron shortage. Yellowing leaves can also be a sign of nitrogen deficiency, it rather depends what the yellowing looks like. Epsom salts is very good when there is a shortage of magnesium, but the likeliest problem with a Camellia is an insufficiently acid soil ph, which will be corrected by Sequestrene. More info on deficiencies and their symptoms here

https://www.rhs.org.uk/advice/profile?PID=456

The writer is asking for a foliar feed.

yes but it depends on why the leaves are yellowing. if they are going to drop then they are beyond foliar uptake. That is why I asked if it was just a few or the whole plant.

Thank you to everyone who replied to my post the information given was invaluable.

I think we must have posted at the same time SBG. In answer to you question there are more yellow leaves than green so I am thinking maybe foliar feeding with Epsom salts and giving the worst affected ones a watering can of sequestered iron as well. Many thanks.

I think that is a sensible strategy Phloxie.