Cook all the vegetables individually until they are just tender. Drain them in colanders and set aside. Transfer all the vegetables to a large bowl and gently toss to mix well.

Put the vinegar, sugar, mustard, mustard seeds and turmeric in a large saucepan and place the pan over low heat. Cook, stirring constantly, until the sugar has dissolved. Increase the heat to high and bring the mixture to the boil. Reduce the heat to moderately low and add the vegetables to the pan. Cook the mixture, stirring occasionally so that all the vegetables are thoroughly basted, for 5 minutes.

Remove from the heat and ladle the pickle into clean, warmed preserving jars. Seal the jars and label them. Store in a cool, dry place until ready to use.