Why not simply invest in some insecticidal (potassium salts of fatty acid) soap that's purposely formulated to be effective as a contact insecticide?

Why not use a 50/50 mixture of rubbing alcohol and water and use as a spritz? - very effective and instant knockdown.

Why not use pure cold-pressed neem oil, which works in so many ways to keep predation in check, and has some residual effects, unlike the soap and alcohol remedies?

Al

Yes, you can buy insecticidal soap premade that works great. I did that one year for aphids. After that ran out, I used some of my wife's soap. She makes soap the old fashioned way with lye, oils and makes it in a pot on the stove. I just soaked some soap shavings in warm water and put it in the empty spray bottle. It worked just as good if not better than the store bought stuff. I dont know about PH levels or anything. Three straight days of using that stuff and it has consistently did the trick. No harm to the plants either. I have seen where others claim that regular store bought soaps work too. Even dish soap when mixed with water.
Bruce
Bruce

I saved this text from a previous post since I plan on giving it a try if/when needed. Scott123456 posted it...

'You can use Ivory dish soap itâÂÂs a white liquid and is not a detergent. I mixed some of that with some alcohol, water, and a couple of cloves of garlic for good measure. I did not have an aphid problem, but I wanted to overwinter my plants without bugs. I sprayed down the plant real good let it dry out and repeated. I never saw a bug and neither did my wife and trust me she was looking real close.'

Update: Found the thread (below)

Here is a link that might be useful: Battle with Aphids

This post was edited by mecdave on Mon, Oct 20, 14 at 12:23

AI, thank you for the advice.

A couple of times I used insecticide from Bayer it was too strong for my chili plants. Since then I started to use many different homemade recipes, such as dishwasher liquid, Olive oil with dishwasher liquid and Castile liquid soap. Neem oil with dish washer liquid got good result. However still I have been trying to find out the best and easiest way to control aphids.

The Neem oil I use is cold-pressed (the sellers claimed), I have suspicion of the quality of the Neem oil I used, even the same source Neem oil the quality are different. The first bottle I used had very strong garlic like smell and very effective. The second batch bottles I bought were not having much strong smell and less effective.

Some of our members recommended to use Castile soap, thatâÂÂs I tried. The source of pure Castile soap I have is only eBay and Amazon, thatâÂÂs also I am not sure they are pure Castile soap.

To get pure Castile soap I made it :) Making Castile soap is also easy, I have all the ingredients and tools at home so just I tried it. The plants I sprayed my homemade Castile soap are not yet get any negative effects.

I never knew to use of rubbing alcohol for plants, I am very interested about it. I will try it, we have different types of rubbing alcohol the one I found in the supermarkets are 93% alcohol (ethanol) and another one is also 93% alcohol (denatured). I will try the first one.

Bruce, I also cooked the lye with oil to neutralize the lye. Some people also made soap without cooking but it'd takes more time to neutralize the lye, source Internet :). To check the neutralization of lye phenolphthalein also use but I did not use it.

Mecdave, many people recommended to use pure soap for aphids, just I mentioned before, thatâÂÂs one of the reasons I made Castile soap too.

I also tried forceful water spray but it ruined the tender foliage and flowers.

I am very interested AlâÂÂs tips of using rubbing alcohol. It could be one of the best, cheapest and easiest way to control aphids.

Thank you everyone for the posts and tips.

Veto

FWIW - the 'rubbing alcohol' I use in the spritzer is 70% isopropyl alcohol (isopropanol) mixed with an equal volume of water. I know they use ethanol in rubbing alcohol, but I've never seen it in stores around here.

A very effective concoction:

1 pint of very hot water
1 pint of 70% isopropyl (rubbing) alcohol
1 tbsp. pure cold-pressed neem oil (Dyna-Gro is a very good source)
1/2 tsp Murphy's Oil Soap or Castile peppermint soap

Add the neem and soap to the hot water. Shake well. Add the alcohol & shake again. Use the mix to spritz the plant, covering all surfaces and making sure to cover undersides of leaves and all leaf axils (crotches). Use it all, same day. It degrades quickly in the light. Keep agitating the mix as you spray. It will tend to resist emulsification.

I avoid all non-vegetable soaps for use on plants - including ivory, which IS a detergent. The chemicals in those detergents break down cuticular waxes in leaves and stems, and most (if not all) are otherwise phytotoxic to varying degrees.

Al

If you want something 'cheap' use 1 drop of liquid dish soap to about 500ml of water and a hot pepper aka habenero or similar. Boiling the water and pepper together, then removing the pepper is better but I just let it infuse for a while.

You have to keep using it though it'll kill a lot of soft bodies.

Al, thank you again for giving me the detail information of making the recipe.

Rubbing alcohol available in the pharmacy is 70% alcohol. The Ethanol 93% is for household rubbing alcohol (for cleaning) :) So I'd use the 70% isopropyl alcohol. The Neem oil I use is from Mother Natures Goodies.

Madferret, thank you for the post. Your recipe is new to me, it will be the cheapest recipe. Before I used water and liquid dish soap without boiling and adding anything else, but the result was not so good.

Veto