Sterilise your jars and lids by washing them with boiling water. Let them cool on a rack and dry them out.
Wash the gherkins thoroughly. Put them into a bowl, mix 50 g salt with 1 litre of water and pour this brine over the gherkins. They should all be under the brine. Cover the bowl with a plate and let them rest for 8 – 12 hours, at best overnight.This is an essential step. The salt will pull out water from the gherkins (i.e. dehydrate them) and thus help them stay crisp for a long time. Don’t skip this step! The next day, pour off the brine and dry the gherkins with a cloth.
Now, cut off the blossom end (that’s the one where there’s no vine attached), because it contains certain enzymes that may lead to mushy gherkins. You can also cut off the stalk end, but that’s optional. I usually leave about 0.5 - 1 cm (0.2 – 0.4 in) of vine on the gherkins.
If the gherkins are very large, you may cut them into slices or sticks.
Wash and dry the dill and carefully remove the flower tips.
Wash and dry the savoury and tarragon.
Peel the onion and cut it into rings.
Layer the gherkins, herbs, onions and spices into the jars.
Put water, vinegar, 2 tbsp salt and sugar into a pot and bring the mixture to a boil. Stir until sugar and salt have dissolved.
Carefully pour the vinegar brine over the gherkins into the jars and close the lids immediately.
Let the jars cool down. Now you can either store them in the fridge for 2–4 months or preserve them in a water bath canner for 30 minutes at 90 °C. That way, the gherkins can be stored for at least a year.