Orange tree

[HPBudlong]

I had a beautiful orange tree anout 15 feet tall with incredible oranges - Valencia - This year it gradually started dying and none of the tree people I got in could figure out why. Any suggestions? It was watered, did not appear to have any insect problems, although some of the leaves were a bit crinkly. Southern Calif, Zone 9.

Helen

[David Ross]

My dwarf 'Robertson' navel orange seemed to decline, starting in the summer of 2003 and continuing well into this past summer. Seemingly healthy leaves would suddenly fall as soon a new growth started. Branches were dying back. It failed to set any fruit.

I sprayed it with Malathion to combat spider mites (mixing some liquid soap with the spray as a wetting agent). I fed it frequently but lightly, using commercial citrus food plus zinc sulfate (which I no longer see in the nurseries); I also gave it occasional small amounts of ammonium sulfate. I pruned the longer branches to ensure the top growth did not exceed the ability of constrained roots to supply nutrients and water. And I made sure the soil was constantly moist without ever allowing it to get soggy.

It is now recovering. I don't know which of my actions is making it recover. However, it stopped dropping leaves; and I no longer see die-back. With winter near, I've stopped feeding because I don't want tender new growth when we get frost. But I'm still watering frequently.

If the weather is okay this weekend, I plant to move the orange into a new terracotta pot. Its redwood tub is rotting away. The tub is cylendrical, with inside diameter and depth both 18 inches. The pot is 17 inches deep inside and slightly tapered, with the bottom inside diameter 16 inches and the top 20 inches; that's 5% less volume than the tub. Yes, I will have to cut away part of the rootball.

[Newt]

Hi Helen, From this site:

"What's causing the leaves of my citrus trees to be curled an crinkled? Two Possibilities: Citrus Leaf Miner Damage ? This insect is the maggo of a tiny fly that lays eggs into the leaves. Maggots hatch from th eggs and "mine" their way through the leaves causing them to cup an crinkle. "Squiggly" lines can also be seen in the affected leaves This insect is not harmful to the health or fruit production o established trees. Young citrus trees may benefit from sprays o horticulture oil which interfere with the fly's ability to lay egg into the leaf. Spray each time a new flush of growth appears. Read th label of oil product carefully, as horticulture oil can burn the leave when applied incorrectly. Leaf Miner Damage

Or Aphid Damage ? Curled, distorted leaves can also be the result o aphid insects. These pests have needle-like mouthparts which pierc the leaves and feed on the plant sap. They always feed on the newest most tender growth. As these leaves mature, they exhibit the damage but by then the aphids are long-gone. Aphid damage is mostly aestheti and can be ignored. If aphids are detected, they can be easil controlled by forceful sprays of water or by insecticidal soaps. Aphid damage"

There are environmentally friendly solutions you can use. Visit thi site once you have id'd your problem.

-- Newt