Does this Naval Orange Tree look OK?

[Homeby5]

Hey guys,
I bought this Naval Orange plant from Lowes three years ago. I live in the Florida Keys and this plant is in a coral rocky soil that gets a full day of sun. We have a lot of plant eating critters with a lot of Iguanas. I planted it in potting soil and keep it watered. I also keep it fertilized with Advocato/Citrus fertilizer.
As you can see..it hasn't grown too much. For perspective the mulched area is 3ft across and it's height is about 3 feet tall. The main trunk (one on right) has almost died but a little life is left and now most of the green life is on secondary trunk. Any ideas what to do? Maybe move it to a pot on the porch? fertilize more or less? Leave it alone?
Thanks

[brian]

This one looks better than the meyer lemon you posted. 

Many of the leaves look small.  My experience has been that when a citrus tree suffers a lot of twig dieback its next set of leaves is undersized.   However, if it remains healthy from that point onward the following leaves will be normal sized. 

Also, it has two trunks.  If this is a grafted tree one of those might be rootstock.  I don't believe navel oranges are typically propaged through cuttings, and it doesn't look right to me to be a seedling.  See if you can find a graft line.

[Homeby5]

This one looks better than the meyer lemon you posted. 

Many of the leaves look small.  My experience has been that when a citrus tree suffers a lot of twig dieback its next set of leaves is undersized.   However, if it remains healthy from that point onward the following leaves will be normal sized. 

Also, it has two trunks.  If this is a grafted tree one of those might be rootstock.  I don't believe navel oranges are typically propaged through cuttings, and it doesn't look right to me to be a seedling.  See if you can find a graft line.

I assume it is grafted since it came from Lowes. I can't see a graft line but it may be under the soil.

[Millet]

The 1st year when you planted a citrus tree it should have been fertilized 6 times equally spaced out during the year.  The 1st year fertilizer program was to stimulate vigorous growth of leaves and branches that will become the framework of the mature tree..  During the 2nd year, a young tree requires to be fertilized 5 times, 4 times the the third year, and then 3 times per year there after.  Was this done?

[Homeby5]

No.....I just fertilized it every few months....whenever I thought about it. No set schedule.

[Millet]

Well the above schedule is the  fertilizing recommendation for Florida citrus trees, given by The University of Florida.  Citrus are heavy feeders, requiring more nutrition then most plants.