This is the recipe and method I use, very slightly modified from a recipe from ‘Booze for free’ by Andy Hamilton (an excellent book, btw). Will also make pure elderberry or blackberry, just use 2kg of one fruit:
2kg blackberries/elderberries (equal quantities)
1.5kg sugar
Half cup of very strong black tea*
4 litres water
Juice of one lemon (I use 1tsp of citric acid)
1 campden tablet (crushed)
1 tsp yeast nutrient
1 tsp pectolase
Red wine yeast
Freeze berries overnight (or longer if still gathering), then put into a fermentation bin and allow to thaw. Give them a bit of a squish to get lots of juice out, but try not to crush the seeds too much. Add the sugar, boil one litre of the water and pour it over, stir until sugar has dissolved. Add the rest of the water (cold) and all the other ingredients. My method differs only in that I leave it all for twenty four hours before I pitch the yeast to give the Campden tablet a chance to kill off any remaining wild yeasts and to disperse.
Let it sit in the bin for three-five days, then strain into a demijohn (I strain it into another bin first using a sieve and a muslin cloth, then pour into demijohn up to the shoulder as I make less mess that way). I have a litre plastic bottle that I fitted with an airlock that I put any excess into, then I top up after the most vigorous fermentation has finished up to the bottom of the neck of the DJ, more or less.
Rack after a month or so, let it ferment out. I’ll usually rack again after a few weeks, perhaps a month or two, maybe again if sediment still forming, then hide it away somewhere dark for a few months with a safety bung in it to clear fully before I bottle. Leave in the bottle as long as possible before drinking; pure blackberry less so, ready and drinkable in six months or so.
*If you decide to make pure elderberry wine, don’t add the tea; elderberry has plenty of tannin already. If you make pure blackberry wine, add more tea!
The idea of the half and half is that blackberry wine can be a little sickly, elderberry can be very tanniny, the two together balance each other out.
Quick to make, very labour UNintensive, but requires patience in spades before you drink it!