You can start with the opposite question: why not?

Much of the environmental damage from so-called conventional production comes from growing large, continuous areas of one crop. A backyard with a few plants of many kinds often has few pest problems without doing anything at all. The gardeners who reach for a spray first are usually those who are unwilling to pull weeds, who will not tolerate cosmetic damage, or who want total control. If you will pull weeds (or smother them with mulch), tolerate a few imperfect fruits, and accept that some crops have an off year, you already have the temperament of an organic gardener.

You also keep concentrated poisons out of your shed, your hands, your children, your pets, and the food you grow. You stop adding those compounds to the wider environment.

If you feed the soil with compost and organically allowed fertilizers, and you pay attention, you often end up with soil that is easier to dig, full of earthworms, loose for roots, and better at holding water and nutrients than a bed run on synthetic fertilizer alone. Conventional methods can be very hard on that soil life.

Organic methods do not automatically make you a better steward than a careful conventional gardener. There are conventional growers who use pesticides as little as possible and care for their soil well. There are organic growers who should not be allowed houseplants. This book is not a courtroom for that debate. It is a practical guide to basic, sustainable organic gardening.