Little tree has a big problem


My dwarf navel orange tree has a water basin around it, but it seems to drain slowly. The trunk is around 10 inches in circumference; the soil is brown clay. Since it was planted four years ago, it gets blooms and some pea-size fruit that drops off the tree. It is 3 feet tall and does not seem to be growing any taller. The ground seems very hard. I can dig down 12 inches, and it gets much harder beyond that depth. I tried using liquid gypsum and citrus fertilizer at the proper times. When the temperature gets near 100 degrees, the leaves start dropping off, and by the end of summer, hardly any leaves remain. What could I be doing wrong? I live in Casa Grande, Ariz. --- Jon


You have a big problem with this little tree, Jon. It sounds as if the water is not even draining through the top 12 inches of soil, and that is not enough soil, even if the water did drain. If you are hitting hardpan (subsoil that water will not permeate) at only 12 inches, the tree will not grow where it is. I am surprised that it has lived for four years.

If your soil is all like this and you want to grow citrus, you will need to grow it in a large container filled with good-grade potting soil that will drain freely. I do not think a tree that has

been in the ground four years can be transplanted, but you can try. Citrus roots usually run deep and well beyond the drip line of the tree. My feeling is that since this poor tree could not send its

roots more than 12 inches down, it probably kept sending them out diagonally, desperately seeking the water it needed. I am sorry I cannot give you a quick and easy solution.


My 25-year-old oleander bushes seem to be dying. They look like they need water, but that doesn't seem to help. What spray can I use to stop this die-back?

---- Ted in Vista


Ted, the short and sad answer to your question is: There is no spray that will stop this die-back. Oleander trees all over Southern California are dying from a disease called oleander leaf scorch. When you say they look as if

they need water, it is true; they do, but they cannot take up water because a nasty little insect has fed on the water-conducting tissue of the tree. This is a short quote from the UC Davis Integrated Pest Management website:

"There is no known cure for oleander leaf scorch. Pruning out the part of the plant showing symptoms may help the appearance of the oleander tree or shrub, but will not save the plant. The bacteria by then have already moved throughout the plant via the xylem, and limbs that show symptoms are only the first to become affected. Research indicates that some cultivars of oleander may express symptoms to lesser degrees than others and may live longer than other varieties when infected."

You can read the whole sad story at



