Hi Help very much needed please, I have a very ill Meyer Lemon, I have had for approx 4 years. I am In Victoria Australia, it is Summer here. Back in October I noticed that some of the leaves where turning yellow. I thought it was lack of food, so I feed it a Citrus food. The 1st photo was taken back in October the 2nd yesterday as you will see there, it is loosing leaves at a great rate- turning yellow and dropping off, some leaves are now developing brown marks. I went to a plant store and they told me that I should not be using citrus food on a container plant as it would and could burning the roots and that I should use a liquid fertilizer called Seasol. They also suggested the I remove part of the soil in the pot and top it up with the one they recommended. The root system looked fine pale in colour and not rotten. So I have been following their instructions for over a week and a half but it doesn't seem to be make any difference. I was watering with grey water as we have heavy water restrictions here at the moment, but they also told me lemons only like clean fresh water. Seems like i may be doing alot wrong. Reading some of the threads here, I was getting myself confused as to what the problem could be. I also read it depends on the rootstock so I found the orginal label which states rootstock Swingle.