What should I use to treat mites on my citrus?

I've discovered spider mites on my satsuma orange tree. What do you recommend I treat it with? The tree is growing in a pot on my porch so I can take it indoors in winter. I don't want to use a pesticide that will ruin the fruit.

Spider mites like dry conditions. Since the satsuma is growing in a pot on your porch, it's probably not exposed to rainfall. When you water, you add water to the pot. Right? So, the leaves are seldom exposed to water. As a preventative measure in the future, spray the leaves above and beneath when you water your orange to discourage the mites.

Spraying the leaves with water, especially the undersides, may be enough to get rid of them. If not, there are two pesticides on the market that might do the trick. One is Monterey Bug Buster. The active ingredient is esfenvalerate - a synthetic pyrethroid insecticide. The other pesticide is Trounce by Safer, the makers of insecticidal soap. Trounce contains insecticidal soap and pyrethroids.

As with all pesticides, follow label instructions.

Another Pest On The Loose: The Redheaded Flea Beetle.

Yet another pest is on the loose, apparently moving southward from New England. Now it's the redheaded flea beetle (Systena frontalis). It has recently become a serious nursery pest, and if it's a problem for plant nurseries, it can become a problem for you.

The redheaded flea beetle munches on roots and leaves of woody plants, vegetables and perennials including crape myrtle, hydrangea, roses, buddleia, forsythia, blueberries, cranberries, cabbage, beans, beets, sedum, salvia, hibiscus, rudbeckia and coreopsis. After overwintering in the soil, the larvae hatch and start on the roots. Heavy infestations can completely girdle plants.

The larvae are slender and white. Adult redheaded flea beetles are about 1/16 inch long, black with reddish heads and have long antennae. As the name suggests, they jump when spooked.

Gardeners probably won't see them when they're feeding in the root zone, but will notice skeletonized leaves from feeding adults. Redheaded flea beetles seem to be more abundant in rural gardens adjacent to row crops such as soybeans and corn.

So far, there aren't any sure-fire remedies for redheaded flea beetle infestations. They might be caught with sticky traps. They feed on certain weeds, so their numbers might be reduced if gardens are kept weed-free. Researchers are working on chemical combinations they hope will do the trick. Systemic insecticides containing dinotefuran and bifenthrin seem to work well. Dinotefuran is pretty expensive.

Systemic pesticides should not be used on fruits and edible plants. Pesticides should be applied in mid- to late spring when larvae are most active. Always follow label instructions when applying chemical pesticides.

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Results of Community Poll Ending Jan. 1, 2013 About Pesticide Preference

Our Community Poll asked the question, "What kinds of pesticides do you use?"

• 50% of respondents use only organic pesticides.
• 50% of respondents use "organic pesticides and chemical pesticides. Whatever works."
•  Zero percent use synthetic pesticides only.

Obviously, gardeners prefer organic pesticides, but 50% of them will resort to other stern measures to protect their crops.

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What is insecticidal soap? How does it work? Can I m ake it myself?

What is insecticidal soap? How does it work? Can I make it myself?

Insecticidal soaps are environmentally friendly formulations made from mineral or vegetable oils that kill soft-bodied insects either by suffocation or destroying their cells. Insecticidal soaps do not leave toxic residues. They must contact the insects to be effective.

Here's a quick and easy way to make insecticidal soap. Mix one cup of cheap vegetable oil with one tablespoon of dishwashing liquid. Do NOT use soaps formulated for automatic dishwashers because they may contain chemicals that can harm plants. Do NOT use soaps with bleach added. Add two teaspoons of the soap mixture per cup of warm water in a plastic spray bottle. Stir thoroughly. Test a bit of the mixture on a small part of the plant to assure that the mixture won't do damage to the plant. Spray only on cloudy days or before dusk. Hot sunlight combined with insecticidal soap can damage plants.