Companion plants

Fine.

People say lettuce can be insect repellent for cabbage. Then I planted seed of lettuce in the plug pots. These kind fo combination is called companion plants. In this case lettuce protects cabbage from insects. There are a lot of other combinations.

Now I am interested in organic agricultural chemicals which is called Azadirachta indica. How to use is to water down its sap by 500 times and splay on leaves. It also protects plans from insects.
This is because time has come to plant baby lettuce and cabbage.