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Bill Rose · 29-05-2007, 06:40 AM posted to rec.gardens

In article ,
zxcvbob wrote:

Red Fox wrote:
"zxcvbob" wrote in message
...
wrote:
On May 26, 1:51 pm, zxcvbob wrote:
I have a rather extensive collection of old bottles of pesticides, but
I'm out of Kelthane. :-( Also, I think "Black Leaf 40" (nicotine
sulfate) is not approved for roses.

What other insecticides are *effective* against mites? Some are listed
but don't work very well because mites are not insects. How about
horticultural oil? I have a bottle of dormant oil spray that I can mix
half-strength for a summer oil spray... Will that work? Thanks.

Bob
Bob, control of mites is possible with Neem oil, insecticidal soap or
a high purity horticultural oil. If you prefer chemicals, miticides
such as abamectin (Avid) or bifenthrin (Talstar) may help. If you use
a miticide, frequent chemical applications may be necessary and not
very effective if plants are not also washed with water.

Periodically washing plants reduces numbers of mites while preserving
their predators. When hosing off the plant, make sure to rinse the
entire plant, top to bottom, as well as the undersides of the leaves
using a hard spray of water. Once spider mites are knocked off of the
plant, they can't crawl back. The watering should be done in the
morning or early evening so that the leaves can dry before nightfall.
You don't want to trade the mite problem for fungal problems!

Hope that helps...

Daniel

Thanks. I don't have any miticides. I think I'm gonna go with the
horticultural oil, alternating every few days with spraying the plants
with high pressure water. I have several insecticides that /might/ work
(diazinon, dursban, and cygon), but more likely they'd just kill any
predatory insects and ultimately make the mite problem worse.

Once the roses are healthy and growing good, the mites will lose
interest in them. But the roses are just now coming up and some are
still stressed-out from last winter.

Bob

Hi Bob,

Why do you persist in exposing youself to poisons?

I suggest you look for a natural insecticide like pyrethrum or Derris
powder.
Not all natural insecticides are very safe but the majority in common use
are far safer than the synthetic insecticides being pushed by the chemical
companies.

I suggest you look for an organic gardening newsgroup. It might even spare
you a big cancer down the road.

Good luck.

RF

I very seldom use poisons; I don't think they are posing any danger
sitting in their brown bottles waiting to be used. I used horticultural
oil on the roses; that is considered "organic". But if termites attack
my house, I'll get out the chlordane (outside, not in the house). If a
sudden plague of bean beetles ravages my garden, I'll be ready for them
with any of a dozen chemicals. But that doesn't happen very often.

People who dump bags of "weed 'n' feed" on their lawns every year scare
me. When the "Chem Lawn" truck comes around, the whole neighborhood
smells like 2,4-d. But I use commercial fertilizer on my lawn -- at
about 1/3 the recommended rate -- and control the weeds mostly by proper
mowing. I put a light application of high nitrogen down in the spring,
then mulch the the clippings to recycle that nitrogen all season, then I
put a light dose of balanced fertilizer down in the fall as a
"winterizer". I mow the grass kind of high to preserve moisture. I
spot treat with 2,4-d when necessary (particularly stubborn dandelions),
but I haven't had to in several years. My lawn is as green as anybody
else's, at a lot less expense and a lot less taxing on the environment.

I don't see anything wrong with occasionally using small amounts of
chemicals, where they are biodegraded rather than running off or soaking
into the ground water.

Bob

Never hurts to see if there is a better way. IPM. Just check it out.
- Bill
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