Orange tree not healthy
I have an orange tree that is unhealthy. Two others are doing very well so the climate is good. (I'm in So. Calif. near the beach) I'm using fertilizer that says "Citrus" on the bag and it seems t work on the other trees as they have a dark green almost blueish color and grow well. This tree does not grow well, the leaves fall off and are Yellow. It looks like lack of water but you see on the photos the grass around the tree is doing OK. I fill the basin around the tree with water a few times a week. The soil drains well here as it is mostly sand. A few years ago when I planted it I used a bag soil mulch-like stuff that was sold as being for citrus and cactus plants. The area gets some sun and some indirect sun. You can see in the photos that I have so many twiggs and not enough leaves. It did resently flower but I dout there will be any fruit I put some photos on "dropbox" here: https://www.dropbox.com/sh/6dqfhmdv5mla3hj/Ns-V-DMMJY
It was worse but I started an aggressive watering and fertile program half a year ago and now it is better, gom of the leaves are green now.
You likely need more information. Just ask.
Here is a link that might be useful: Photos