Wash cauliflower and break into flowerets. Scald the onions, peel and slice. Mix with cauliflower and salt and let stand overnight. Drain and rinse in cold water. If too salty, soak one hour in cold water and drain.
Combine the sugar, turmeric, mustard seed, celery seed and red pepper in an 8-quart kettle. Tie the whole cloves in a cheesecloth and add. Stir in the vinegar and water and boil 5 minutes. Add the cauliflower and onions and boil until tender but still crisp, or 5-10 minutes.
Remove and discard cheesecloth bag and red pepper. pack at once into hot sterile jars and fill the jars with the boiling liquid. Seal at once.