How to make
Clean and wash the blueberries well. Boil the water with the sugar in a pot.
When it boils, add the blueberries then. Leave it to boil on the stove, until it thickens.
Stir from time to time with a wooden spoon and remove it when foam is formed.
Check whether the blueberry jam is ready by dropping a drop on a plate and if it does not spread, then it is ready.
Add citric acid, stir and then remove it from the heat.
Distribute it into dry jars, close them and turn them with the lids facing down.