I use a combination of wasps(calcid I think they are called),ladybugs, green lacewings and mantis.
Ladybugs do good in the spring and fall when it's cooler.
They get so thick there will be several adults and larva on each plant.
When it gets hot they dissapear until fall.
The mantis are around all summer (but they eat anything including ladybugs and lacewings...)
Wasps you get from plants at the nursery,they are really expensive to buy.
Find a plant with aphid mummies on it at the nursery and take it home.
They die when it gets hot.Great year round inside.
Lacewings are better than anything else.
They don't wander like lady bugs.
But you can't have ants.Ants love Lacewing eggs.
Like lady bugs,they have to eat pollen to lay eggs.You can google a home made substitute or buy the food online.
A place that raises and sells bio bug control is close by so I just go there when I need something.Tip Top Bio controls in woodland hills CA.
It took 2 years to get a resident population.
These bennificials seem to take turns being dominant in the garden.
First are the Mantis hatching early spring,then the ladybugs after that the lacewings.
The wasps are around inside year round but die once the weather gets over 80 outside.
Right now the Mantis are getting ready to make egg cases and are pairing up(during the year they are territorial and would kill each other over territory) and the ladybugs and lacewings are all over the place.
Wasps are inside until it cools then I'll put a couple plants outside with mummies on them for my winter crop.
I never had any luck with soaps or neam.
DE and Boric Acid powders work great on the ground around my pots for other bugs.
I use Caterpillar Killer for moths and butterfly caterpillars.
Only bug I have real problems with is Japanese beatle larva and leaf miners.
I'm trying Nematodes for the beatle larva/grubs.
Caterpillar Killer is supposed to do in the leaf miners that are from moths but some leaf miners are from a beatle and it won't work.
Hopefully the mantis will get a taste for beatles instead of lacewing and ladybug larva.
I also see a few syrphid fly larva cruising around that might have come from the nursery on a plant-greenhouse growers use them.
They look like a cabbage moth caterpillar but are brown and have a pointed head with feelers.
They look like they only have 2 back legs.
Travel faster scouting out aphids on top and under leaves.Make cacoons on top of leaves,not hanging like butterflies etc.
Wasps
Syrphid larva(mine are brown)
http://insects.tamu.edu/images/insects/common/images/cd-43-c-txt/cimg233.html
My flies are silver and black rather than yellow and black.There are a bunch of different kinds...
http://insects.tamu.edu/images/insects/common/images/cd-43-c-txt/cimg232.html
Mantis
http://images.google.com/images?hl=...&sa=X&oi=image_result_group&ct=title&resnum=4
Eggs like I get
http://images.google.com/imgres?img...ggs&hl=en&sa=X&um=1&ei=mh-iSvGmHIevtwfk_tWbBQ
green lacewing
http://www.vegedge.umn.edu/VEGPEST/beneficials/glw.htm
Ladybug-eggs,larva etc.
http://images.google.com/images?hl=...&sa=X&oi=image_result_group&ct=title&resnum=1