I am not a Buddhist monk (I am a yogic monk) but this question was asked to me recently and it deserves an answer.

Obviously if you have a pest in your garden you have to make a choice whether you are going to take action or not. To kill the pest would seem to go against “non-harming” which is basic to many Eastern religions and philosophies.  Not hurting others by thought word or deed is known as Ahimsa, and it is an important value in Buddhism, Hinduism, Jainism and other faiths.

The Jains took Ahimsa to its limits and some of them said that any kind of agriculture is forbidden because when you plow the soil worms and other small creatures are bound to be killed. So what did they do about this dilemma? I think in most cases they hired other people to plow the soil for them!

Clearly this is no solution to the problem. The solution is to have a more practical interpretation of Ahimsa. Life feeds on life. Whenever we want to sustain ourselves we have to take some life, whether it be an animal or a plant. Yogis say that it is best to avoid killing animals or living beings where consciousness is developed, and that is one of the reasons why they are vegetarians.

Furthermore, Ahimsa doesn’t mean living a passive life and letting others attack you without any defense. If a person comes to take your land, burn your house or poison you, you will have to defend yourself if you wish to continue living. The person who comes to attack you is surely an enemy, and if you defend yourself it is not against Ahimsa.

Similarly, if your food supply depends on a field of grain and vegetables, an animal or insect that comes to eat and destroy that field is also your enemy, just as surely as a person who comes to pillage your land. If you take forceful action to defend your food, and thereby kill some of the pests it is not against the true spirit of Ahimsa. You have used force to continue your own life, not to inflict harm for no reason at all.  A strict interpretation of ahimsa, not allowing you to kill mosquitoes that spread malaria or to kill pests that eat your food, would be a folly at best and hypocrisy at worst.

So, if that Buddhist monk is truly depending on his garden to provide his livelihood, he could kill the pests in the garden. If the garden is only ornamental or done for a hobby, he might just let the worm or insect enjoy a share of the fruits and veggies and not worry too much about it. But if you are really curious about it, the next time you should ask a Buddhist monk.