Homemade Soap as Insecticide?

I've read that soap is an insecticide but is homemade soap made from just lye and fat an effective insecticide too?

Soap is usually considered an insecticide because it causes insects to dry out- and so they die. So any soap would do this, hand made or not.

Charli Wilson wrote:Soap is usually considered an insecticide because it causes insects to dry out- and so they die. So any soap would do this, hand made or not.

Just curious: What is it about the soap that dries them out? Is it the lye? And if so, would a soap with a greater amount of lye be even more effective?

Soap causes oils and fats to break up, so causes the wax on the insects skin to dissolve- and so they dehydrate and die- it only really works on soft-bodied insects (like aphids, whilst things like ladybugs seem to be unaffected), and it only works whilst the soap is wet (once dry it becomes harmless). Afraid I don't know if a lye-heavy soap would be any better than regular soap (my knowledge of chemistry doesn't stretch quite that far!). People claim that adding various essential oils to their soap makes it a better insecticidal soap (I think things like tee-tree are meant to hang around on the plant and further repel insects, and some essential oils are considered insecticidal).

I just spray washing up liquid at my aphids... I've never actually tried the essential oils thing!

Charli Wilson wrote:Soap causes oils and fats to break up, so causes the wax on the insects skin to dissolve- and so they dehydrate and die- it only really works on soft-bodied insects (like aphids, whilst things like ladybugs seem to be unaffected), and it only works whilst the soap is wet (once dry it becomes harmless). Afraid I don't know if a lye-heavy soap would be any better than regular soap (my knowledge of chemistry doesn't stretch quite that far!). People claim that adding various essential oils to their soap makes it a better insecticidal soap (I think things like tee-tree are meant to hang around on the plant and further repel insects, and some essential oils are considered insecticidal).

I just spray washing up liquid at my aphids... I've never actually tried the essential oils thing!

I'm using some soft soap (store bought) in a mix with onions, garlic and peppers and it's working great. Wish I would have known about it last year when my garden was pillaged and decimated. Now, that I see it works, I want to make my own soap so I don't have to wonder what chemicals are going on my plants. Anyways, thanks for the info. Good stuff to know!