Yeah I have to agree, how is it possible to keep them free of pests unless you camp in the garden permanently???
These are my steps (All obvious ones which most gardeners take regardless of organic or non-organic approaches in my experience)...
1.First and foremost keep them as healthy and well fed as possible (starting with good soil) and keep regular amounts of foliar sprayed seaweed extract on them and make sure the soil has plenty of good bacteria/fungi.
2.Don't allow them to get too stressed (to hot/cold/wet/dry)
3.At first sign of problem try to figure out what is causing it meanwhile isolating the plant (if possible) from any others.
4.Then if needed use many of the organic sprays options available (NEEM, my own homemade Garlic-Soap Spray, copper, iron chelate, derris dust are all organic and easily sourced and used) or even go biological control if needed.
Those are my steps I have always taken with my gardens but I don't think it would be any quicker for me personally to use non-organic approaches
Except for the fact it may take longer to get things back in balance/under control with organic sprays etc it simply takes a more systematic approach to each issue in my experience and gives me more of an excuse to spend time with my plants
I also think Organic gardening is something which is easier/best done over a few years in the same garden/soil where you can build up the soil and plant companion/beneficial plants yo complement your crops and get things in balance before you start each season.
Simply my opinion though and its by no means right for everyone