But what if the tree aleady has an ample supply of magnesium? Applying this and that in a hope of finding the answer can cause a more complicated problem than the tree already has, and usually does not cure the problem. Maywren, has already fertilized with a fertilizer that contains trace minerals. Besides a magnesium deficiency shows definite leaf patterns, and would be easily identifiable. Actually, the proper method is to do an analysis. As you live in Florida, take a soil and or leaf samples to your local county agent for testing. Then in a couple days you will certainly know what's going on with the tree and can shortly correct it. It is really almost impossible for us on the web to know what is wrong with the tree from the information given. - Millet

TIA, there is an excellent method developed by American universities for checking the EC and PH in a case like yours. It is the Pour Thru method. It is not destructive, easy and accurate enough, specially for checking PH. http://www.ces.ncsu.edu/depts/hort/floriculture/hils/HIL590.pdf https://m.youtube.com/watch?v=R6OzTerLzlo For checking PH, you can use PH strips, are cheap and accurate. You can find it in ebay or laboratory suppliers. Buy strips up to PH 9 or so. One important thing about Pour Thru method, when you are first watering for soil saturation, no matter how much water you apply. But one hour later, for collecting leachate for checking, you have to apply just water to collect 50 ml, no more water!! Or you will dilute the leachate and will alterate the result. Remind, just a leachate of 50 ml!! When collecting leachate, try to elevate the container from the saucer. The bottom of container can have accumulated salts which can alterate the result. You can use two piece of wood or plastic for separting the container from the saucer.

Janette: You have been having hot temp, leaves are wavy, and water has not drained out of the pot so you may be under watering, It is hard to tell. This is how to tell if the tree needs watering: take a 1/4 inch dowel sharped to a point or a shish kabob stick and stick into the soil all the way to the bottom. Wait about 5 seconds and pull it out. If there are soil particles sticking to it or if it feels cool and damp then it does not need water. It is important to let water drain from the bottom, to prevent buildup of salts. Laura: Some of my trees do that, too but the leaves are not yellow ,they are not dropping leaves and they seem to be OK. I don't know why they do that. I admit it does worry me sometimes. It's like taking care of kids, isn't it? Like when they get a fever and you worry.

Jack's Pro water soluble fertilizer (25-5-15) once in two weeks, a spoonful dissolved in a gallon of water, my trees get 5 gallons each. And also Dyna-gro Pro-tekt silicon supplement. I have also been told that buying Ammonium sulphate would be a quick cheap way of adding nitrogen, but I needed the micro-nutrients as well. I have noticed that the folks who have their plants in containers also add epsom salts and vinegar!