How can I eliminate spider mites?

August 2, 2006 11:27 AM

I've been battling a spider mite infestation on my Angel Datura tree, which lives outside year round. I've tried a few different remedies, but nothing seems to work for very long.

So far, the remedies I've tried include:

1. Repeat applications of garlic-water tincture, canola oil-water mixture, and then dishsoap-water mixture. All of which had small control effects but no permanent cure.
2. Insecticide spray (pyrethins), several treatments. No change.
3. Physical removal of mites with damp cloth, spraying water on leaves as often as possible. Again, controls the population but doesn't get rid of them.

I've checked out this thread, and next I'm trying a Neem or Orange Oil treatment. I've also repotted and fertilized and trimmed off the more affected leaves and branches. I'm getting ready to burn the tree just so the mites don't win.

Does anyone have suggestions of things that have cured their plants? (note: I can't use predator mites because of the expense.)

posted by unknowncommand to Home & Garden (7 answers total)

Spider mites hate cold water. They love hot, dry conditions. So if you can spray your tree with icy water a couple of times a day every day for a week, they may leave on their own. You might lose some leaves from the coldness of the water, but no permanent harm should come to the tree. They just detest icy cold water.

Also see my comment here, which probably also applies to spider mites and is probably worth a shot.

Do they have any natural enemies? Lady bugs? Praying mantises?
posted by iconomy at 11:46 AM on August 2, 2006

My girlfriend uses Lacewings to get rid of spider mites, aphids and other bugs in her garden full of very rare and unusual plants. She is very particular about not using pesticides and after much research and trial and error found these to be the solution that worked best in her garden.

She orders them online for about $15-20 for about 2000 lacewings :)
posted by hellhammer at 1:21 PM on August 2, 2006

Neem oil always worked for me and hard to get rid of scale bugs on orchids.
posted by wavering at 1:26 PM on August 2, 2006

A great resource for tree pests/problems can be found here
posted by tj at 2:09 PM on August 2, 2006

I second iconomy and hellhammer with the use of lacewings and ladybugs.
posted by snsranch at 4:47 PM on August 2, 2006

Several years ago my wife had a jade that was overrun by spidermites. She finally trashed the plant after saving two or three bits to root. The resulting plant is doing well fifteen years later.
posted by pointilist at 4:54 PM on August 2, 2006

You might try crushing 3/4 of an aspirin per gallon of water and applying that to the plant. I use it on my plants and it helps them stay healthy. That and regular applications of fish emulsion. It might be worth planting some garlic under the plant also. Some of my finikier plants like old coffee grounds.
posted by livinginmonrovia at 5:22 PM on August 2, 2006