I like the Bayer as a systematic. Use a water spray on the flower itself to wash off the adults and continue alcohol dabbing on the stem until the systematic kicks in.

Sorry for intruding since I am a rose person, but we do have aphids infestations too. Safer Insecticidal Soap will knock 'em dead!

Maybe you can use a spritzer and spritz the alcohol where the crannies are or use a qtip for the dabbing? To be honest I am very surprised to read about alcohol, it dries out human skin, and I would be worried that it would dry out the flower too, but I'm just an ignoramus. I only know roses, not orchids...hmmmm. We in the rose world never use alcohol to kill aphids. A handful of us use hot wax pepper spray to deter them on our buds and blooms, but to actually kill them we use Safers Insecticidal Soap or smoosh them by running our hands over them if they're on a leaf or a stem.

By the way, Neem oil is not too "heavy" for a flower. Blooms don't care one whit. If a rose can take it, I would think likewise an orchid. But be very careful if your orchids are outdoors. Neem oil (if it contains pyrethrins) need a drying time of 4 hours or else it will harm a bee that lands on it(however it doesn't wipe out the entire hive like Sevin will-it just kills on immediate contact if it hasn't dried), so I would only spray in the late evening when the sun has gone way down. If your orchids are indoors, I wouldn't worry about any of this.

Soapy water will wash aphids right off, softens their exoskeleton, and they drown. It may harm flowers less than Safer's would. Don't know, never used Safers on flowers. It's a great aphid killer and I've used it safely on buds, but...

Aphids give birth to *pregnant* young, so one becomes a thousand in a few days. It may not be worth it to hold back on a treatment to preserve the flowers.

You will have to repeat the treatment several times every three days or so to get every last one.

Actually mehitabel, Safer insecticidal soap is much safer than homemade soapy water. The reason why is because the manufacturer knows the ideal mix. Often people just guess the ratio of soap to water and they guess wrong! Soap if the wrong kind or too strong of a mix can burn the plant. But if soapy water does have the right ratio, it too can work--to me the main advantage is the price tag, hee-hee!

I use Vermi-Liquid which is the liquid from a worm bed. It is often called Worm Tea but not the compost in water type. It has to be the liquid drainage from the worm beds.

It has a chemical called ceitanese in it that is harmless to us and pets. It has only one characteristic and that is that it dissolves ceitain. Ceitain is the skelton of an insect and fatal to them. Equally effective on all nasties - thrips, mealies, etc. making it an orgainic pesticide.

With aphids is is irritating and they leave probably before they die. I have eliminated hundreds from a rose bush with one spraying.

Best bonus is that Vermi-Liquid adds moisture to the flowers and can extend their beauty as they do not get dry marks as fast. Studies have shown they can help retain 30% more moisture in the roots of the plants. It is a great product.

Also there are millions of microbes in the liquid which helps the plant to break chemical fertilizers down into forms the plants can absorb.

mehitabel...I did go with your advice to not hold back treatment in the hope of preserving the flowers.

I used a 50/50 mix of 70% alcohol and water, applied with a *fine mist* sprayer to the entire plant...flowers, stem, leaves and fibrous potting medium. Have kept up with probing the innards of the individual flowers with alcohol soaked q-tips. It is now day #3, the flowers have not shown any stress from the repeated treatment.

Shining a light through the translucent petals, not seeing anymore adults. I will taper off on frequency of treatment now to every other day. Hopefully I can win the battle with those thousands of eggs getting ready to make their debut.

Will post followup in a few days.

Thanks...