Butterflies can be friend or foe of organic gardener

I HAVE an organic vegetable garden. Organic gardening, according to the textbooks, is supposed to create harmony between nature and the gardener. You exercise a bit of give and take and achieve a state of balance in which chemical pesticides and fertilisers become unnecessary.

This actually works a lot of the time — but not all the time.

Last year I went on holidays, took my eye off the ball for a few weeks, and was invaded by butterflies. By the time I discovered the caterpillars it was too late. I lost all the winter cabbages, the sprouts, the kale and the winter broccoli.