There are many kinds of walnut trees, and my understanding is that the leaves from any variety can be used for making wine. A pint of packed leaves is all it takes. Some of the majestic walnut trees of East Texas could supply enough leaves for thousands of gallons, but that might be over-doing it.
Put the water on to boil and stir the sugar and honey into it until dissolved. When boiling, remove from heat and skim scum off surface. Put leaves in primary and pour water over leaves. Cover primary and set aside 24 hours. Strain leaves from water and stir in acid blend and yeast nutrient until dissolved. Add activated yeast. When active ferment dies down (5-7 days), transfer to secondary and fit airlock. Put in warm place until fermentation completely stops. Rack into santitized secondary, top up and refit airlock. Move to a cold place for six months, checking airlock occasionally.Sweeten to taste, rack into bottles and age an additional six months. [Adapted from recipe by Women's Institute Members' Home Made Wines, Syrups and Cordials, 1954, London]