In the 1990's a study was done by the U.S. Department of
Agriculture using simple soap spray. They took sunflower
and safflower oil--use either one--and mixed one cup of the
oil with one to two tablespoons of liquid dishwashing soap--
I've always heard Ivory was the best to use--and then mixed
in one cup water. Place this in a spray bottle and finely mist
the bigger seedlings and transplants. It's amazing that this
simple spray reduced the amount of pests so effectively! It
helped with whiteflies, aphids and spidermites. They did find
that the spray damaged squash, cauliflower and red cabbage
plants-so stay away from those. Also, it should be reapplied
in about 2 weeks.
MORE ON SOAP SPRAYS FROM THE HERB LADY
I have been using the oil/soap/water sprays for years. Our aphids
are really a problem here in the desert southwest in the spring and
again in the fall. To be really effective we have to use the spray
every 5 days (3 times in total) to interrupt the egg cycle (for egg
baring aphids - we get a particularly pesky one that bares live and
can crown a plant in 2 days if you don't catch it). The first spray
catches the adults, the 2 the new hatchlings (cause the spray does
not damage the eggs usually), and the 3 one catches any leftovers.
I like to use Dawn (I figure if it was good and safe enough for the
Exxon Valdez birds it is okay for my garden). You have to keep
shaking it to keep it mixed, getting the undersides of the leaves. I
try to be careful and not hit any beneficial insects because it can
kill them too. Our sun is so intense with the oil and water droplets
causing sunburn, I recommend that the plants not be sprayed
until twilight or at least wait until the sun is off the plants in late
afternoon.
The good news this year is although the pesky bug population is
up, so are the ladybugs in gardens where no one has used
chemical sprays. New-to-organic gardens occasionally have
problems understanding that the ladybugs and fellow beneficials
need something to munch on to draw them to your garden.
Catherine uses 1 teaspoon each
vegetable oil and Dawn dish soap to one quart of water, or 1 tbsp.
each of the vegetable oil and Dawn dish soap to a gallon of water.
Visit her website here.
