To start your way to establish happy trees, you must rake all the gravel away from under the trees. You’ll probably find there is a layer of plastic under the gravel and that has to go the way of all flesh as well.
You have probably uncovered some small roots on the surface and they may be removed without ill effects to the tree.
Now rake dirt away from the trunks to create a “bowl,” lowest at the trunk, grading it all the way out to the outer periphery of the foliage.
This exercise is to facilitate space for frequent flooding of the trees. Citrus is not supposed to have daily watering like the rest of your garden (I have been told).
During the period of day after day of 100 degrees or more, you flood the bowl twice a month, slowly over a period of one hour or so.
During the cooler period of the year, I flood only once every month.
The idea is to train the trees to reach deep down into the moisture, thereby being much more resistant to dry periods created by absence of moisture or forgotten watering. (We are fortunate enough to have a clay barrier around three feet down, preventing the watering from draining away).
Fertilizing correctly and adequately is of utmost importance if you want 100 percent results. Use approximately one gallon of dry fertilizer per six to eight foot trees. I have found that 21-0-0 is very effective as general use. Off and on, I get a bad conscience and use more complicated feeding and switch to 13-10-4 and have not had an argument from the trees.
Any time of the year, I trim off long, new shoots without ill effects, thereby leaving more power to the productive branches and it also simplifies the harvesting of your fruit.
The sweetness of the fruit produced by this system is beyond belief. I just picked my last grapefruit and it is by no means my largest one this year. Grapefruits the size of the Hawaiian “Pomelo” are quite regular. The one depicted measures 19 inches in circumference.
Not only do we grow huge fruits, we produce literally hundreds per year! I tried to count one year and got to over 300!
When your trees have reached what you consider to be “your kind of tree,” you may keep the top trimmed without ill effects.
If you need help contact Svein Jenshus at 480-895-4995; email firstname.lastname@example.org.