Wash the herbs, pluck roughly, put a little aside for garnishing. Put the rest of the herbs into a mixing cup. Wash the cucumber, cut off 1 thin slice and cut in half. Put one half aside.
Using a zest ripper, pull thin zests from the cucumber to garnish. Peel the rest of the cucumber, cut it into small pieces and add to the herbs. Add the kefir and puree finely with a chopping stick. Season to taste with Worcester sauce and salt.
Cut half the cucumber slice at the skin and put it on the edge of the glass. Pour kefir into the glasses, arrange with the cucumber zests, remaining herbs and 2 of the halved grissini stick.