Prep the veg from the cucumber down to the onions.
Put in a large bowl or pot, that you will have room for in fridge, several if needed.
Mix vegetables well with the salt.
Put vegetables in fridge for 12 hours. Stir or toss occasionally if desired.
Drain, rinse and drain again.
Mix everything from the turmeric down to the flour in a large pot. Whisk in the vinegar 250 ml (1 cup) at a time, then add the water, sugar and the garlic.
Bring to a boil while stirring frequently, then reduce to a simmer until it's thick enough to start coating a spoon -- about 5 minutes. Whisk or stir frequently to avoid burning at the bottom.
Add the drained veg to the mustard sauce in the pot, and simmer for 20 minutes counting from the time you added the veg to the sauce.
Put in your choice of the following jar sizes: quarter-litre (½ US pint), half-litre (1 US pint), or litre (1 US quart.)
Leave 2 cm (½ inch) headspace regardless of jar size.
Debubble, adjust headspace with sauce mixture.
Wipe jar rims.
Put lids on.
Process in a water bath or steam canner.
Process all jar sizes for 10 minutes; increase time as needed for your altitude.