This is still manganese deficiency, not magnesium. That is traditionally our issue here in S. California. See that brown tip? The classic picture of manganese deficiency is the leaf starting to yellow from the tip to petiole, and the tip can then sometimes turn brown. Instead, try a foliar application of Grow More Citrus Grower's Blend. You can apply once a week until you start to see things green up. Another option you can use is Gro Power All Organic Soil Conditioner, that has a very large amount of humic acid in it, which will help bring down your pH. Apply that, as well as Gro Power Citrus & Avocado Food. Top with about 2 to 3 inches of compost and finish off with about an inch layer of wood chip to help conserve soil moisture. Water in gently and well. That will help. As our soils warm up, and with the addition of the soil conditioner, the roots will be able to absorb the micronutrients eventually, and the foliar micronutrient application will get you through. This is a classic issue for us in S. California. See the link I've provided for you below.

Patty S.

Here is a link that might be useful: UC Davis: Citrus Nutrient Deficiency Symptoms

Thanks Patty so my other tree satsuma didn't have magnesium but manganese deficiency?

I sprayed the leaves with the below info you told me week or so ago.

Thanks ;-)

It's really manganese out here, and not magnesium. That was my fault Monsoor, sorry! My recommendations will help that I've given you. I have the same problem where I am in N. San Diego county.

Party S.