natural pest control
It really is not a good idea to use chemicals to control pests and weeds in the garden or veg plots. This causes a long term imbalance, starting with the soil - and eventually the chemicals will reach you via the food you eat.
The best and most natural way to control pests is to encourage predators into your garden. Last year I noticed I lost very few seedlings to slugs and snails. I use to have a length of wood across one patch which I use to walk across - and found that toads would hide beneath it. The toads would come out at night and eat the slugs. This year I'll provide as many mini habitats as possible for toads to hide under.
Even in the smallest of gardens or allotments, and a small pond - or even a bucket of water - will attract wildlife. Another idea would be to leave a square meter (or yard) of grass uncut allowing the grass to grow wild. These small acts help kick start a process of encouraging wildlife into the garden which will eventually encourage predators. Ideally toads, hedgehogs and slow worms are the critters you want to welcome.
two broken 'rhino tubs' which filled with rain water - this is now full of life
in my polytunnel there are many toads hiding under pots and beneath grow bags