pests Aphids AND Mites: Best mode of attack?

Roguejim said:
So what you're saying is that pyrethrins kill lady bugs? 
 
How long will pyrethrins remain effective before I can reapply?  They were sprayed at dusk.  I'm talking a heavy aphid infestation.
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Pyrethrin is considered broad-spectrum and will kill most insects it comes in contact including ladybugs at the right dosage ...
Pyrethrin is a contact poison that apparently also has insect repellent properties , however because of its rapid degradation under UV it will only be effective for a few hours in daylight (so in your case you could probably assume it will have stopped working on any new insects within 24 hours)
I would wait 5-7 days before applying again for the health of your plants and because anything sooner is a waste of time. You should see a huge difference anyway ... aphids aren't that hard to kill if your coverage is sufficient. In fact I think pyrethrin is almost overkill for aphids alone .. dish soap is usually enough.
 
I had a horrible problem with aphids earlier this year.  My final solution was to lock my young plants in a tent with 3000 ladybugs for 4 days.  It worked like a charm.  I dont know if your plants are in containers or in ground, but if you can trap the ladybugs, I would advise picking some up.
 
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This has been a good thread on pesticide. I bought some pyrethrin to keep up my sleeve in case the ants decide to keep farming aphids on my peppers now that my bait sunflowers have been pulled.
 
for information if you are interested...I posted this originally in July 2012...
 
a while back, I did a population trend for aphids based on their general reproduction numbers, eggs laid, days to hatch, days to maturity after hatching....it blew me away...it is a kind of geometric progression...

as you can see if you don't get to aphids by day 21, you're plants are essentially goners...I started with one aphid...after day 30 wow...bumping 100,000 and another week, you are in the millions...

to me the key here is day 21...the "knee in the curve"....if you can catch them between day 14 and day 21, you got a real chance of stopping an infestation before it gets out of control...
 
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AlabamaJack said:
for information if you are interested...I posted this originally in July 2012...
 
a while back, I did a population trend for aphids based on their general reproduction numbers, eggs laid, days to hatch, days to maturity after hatching....it blew me away...it is a kind of geometric progression...as you can see if you don't get to aphids by day 21, you're plants are essentially goners...I started with one aphid...after day 30 wow...bumping 100,000 and another week, you are in the millions...to me the key here is day 21...the "knee in the curve"....if you can catch them between day 14 and day 21, you got a real chance of stopping an infestation before it gets out of control...
 
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Very enlightening post AJ...thanks for posting ...
 
Alright, I sprayed the plants heavily with pyrethrins last Sunday evening. Bonide has told me I can reapply the pyrethrins every 5-7 days. Can the plants handle such a regimen, every 5 days, and for how long? I was thinking I could alternate every 5 days between pyrethrins, and soap/water. Any opinions? I'm not sure how long to keep either treatment going.
 
I also had a bad aphid infestation early this season. Ladybugs tore through my garden in one day and killed almost all of them. Pretty amazing. Place them on your plants at dusk and they'll stick around. 
 
Now, it looks like a lot of the plants are developing rust on the leaves.  I wonder if this is some sort of side effect from the pyrethrins?  It's been hot lately (90Fs), but I sprayed after the sun went down.
 
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