Fill a large canning pot with hot water and place a rack on the bottom. Bring it to the boil. Wash five* 500 ml (pint) canning jars with new lids. Make sure the rings are in good shape, ie. no rust or dents. Add a splash of plain vinegar to the canning pot to prevent hard water marks on the jars.

Put the clean jars in the canning pot and boil for 10 minutes to sterilize the jars. Turn the heat off and leave the jars in the water to keep hot.

Put the lids in a small pot with water and bring to the boil about 5 minutes before you will be using them. Let it simmer for a few minutes and then turn the heat off, also keeping the lids warm so that the rubber edge remains soft.

Add all the ingredients to a large heavy-bottomed pot and bring it all to a rolling boil. Stir often to prevent scorching and skim off any foam that develops.

Boil for approximately 15 minutes for a thin syrup. Boil for longer for a thick syrup or a more of a runny jam consistency. You can put some on a cold plate to see how runny it is. Keep in mind that it will thicken slightly as it cools. If you choose to omit the water it will take less time to get to the desired consistency but it does effect your yield as does how long you boil it for. Less time means there is more liquid which means a slightly higher yield.

Remove the jars from the hot-water bath and place them on a board covered with paper towel. Fill the jars with the hot preserves using a funnel. Leave 1/2" (1 cm) headspace. Use a chopstick or dull plastic knife to dislodge any bubbles that may be trapped amongst the preserves.

As you fill the jars, bring the canning pot back to the boil.

Wipe the rims with a clean, damp cloth and place the warm lids on the jars. Put the rings on and tighten the rings just until you meet resistance (aka 'finger-tight).

Place the jars in the canning pot, put the lid on the pot and bring it to the boil. Once the water is boiling, put the timer on for 15 minutes.

When the timer goes off after 15 minutes of processing time, turn off the stove and remove the lid from the canning pot. Let the jars sit in the water for 5 minutes before removing them and placing them on a board with a tea towel or paper towel.

Let the jars sit undisturbed on the counter for 24 hours and then check to see if the lids have all sealed. Enjoy any jars of preserves that do not seal within a couple weeks and store those in the fridge. The jars that seal are good for up to a year and store them in a cool, dark place.

You will yield 4.5 litres of preserved blueberries (less if you omit the water). More if you boil the preserves for less time before adding them to the jars.