LindaTX8 said:French Marigolds and Mexican Marigolds have some beneficial effects. But don't expect them to totally keep insect pests away! They're really not that good, just useful as one tool among many other things you can do.
http://eartheasy.com/grow_nat_...
@LindaTX8 - Thanks very much for this link. I found it helpful and informative.
Regarding slugs and snails: after rain or watering, I find many snails especially, on the move. Sometimes there were 30 or 40 on the concrete patio surrounded by my garden in Robson. Since I feel responsible for introducing them in my garden by purchasing plants from the coast (Vancouver), where eggs can lie in wait in the pots, I gather up the snails in a one gallon bucket usually 20 to 50 at a time. I boil a kettle of water, visualize an instant transition for them to a better after-life, and pour the boiling water over them. I feel that an instant death would be preferable to a lingering death with a saucer of beer, or diatomaceous earth or organic sprays or eggshells. Within 3 to 5 seconds, of the boiling water surrounding them, they are finished. After the water has cooled, disposal can be done in a remote part of the property, or in a bag in the garbage.
I'm sorry if I have offended anyone by this description.