Rotate crops; destroy infected garden debris.

Plant crops affected by blight at a reasonable distance with good airflow

There is not much that can be done once an infection is spotted – apart from a swift harvest of unaffected produce, removal of whole plants and sanitary disposal of all foliage in household rubbish

If you add infected foliage to your compost heap you will spread infectious spores through your compost

In the case of potatoes, if you spot blight soon enough, you can remove all foliage and then wait a week before digging up the potatoes themselves underground – they should still be edible