For plums ...
http://winemaking.jackkeller.net/reques12.asp
For crab apples ...
http://winemaking.jackkeller.net/reques40.asp
Or, if you want to go both ways at once, here's one I cobbled together from the above two ...
3lbs plums
2lbs crab apples
Juice of half a lemon (plus a bit more)
½ cup strong tea
Wash apples well. Quarter them, remove cores and place in cold water acidulated with juice of about ¼ lemon. Don’t worry if the apples begin to turn brown. Cover and leave for 12 hours, stirring now and then.
Next day, stone the plums and place in a bucket (food grade), pour a kettle of boiling water over everything, cover and allow to cool. Meanwhile drain the apples, place in another bucket and smash away merrily with a bit of wood (or a paint mixing attachment on a power drill). You are NOT trying to achieve a puree – just a break-up. Add to the cooled plums.
At this stage, you SHOULD add pectic enzyme to get rid of any pectin which might cause haziness in the finished wine. If you have it, add a level teaspoonful, make sure the fruit is covered with water (just) stir and leave for 24 hours. If you don’t have it, don’t worry – the wine may end up hazy, or it may not, but it makes no difference to the taste.
Dissolve 2 lbs (just less than a kilo – what the Hell; bung in the whole kilo) of sugar in a kettleful of boiling water – stir until it’s clear then allow to cool. When cool, add to the fruit in the bucket together with the juice of half a lemon and a half-cup of strong tea. Add yeast (a level teaspoon of wine yeast or, if you must, some activated bakers yeast). If you happen to have yeast nutrient, add a spoonful of that too. Stir, cover and leave in a warmish place. After a while, bubbles will start to rise and, gradually, the fruit will form a cap on top of the liquid (you’ll know what I mean when you see it). Every few hours, break up the cap and stir it in to the liquid. Do this for three days. After that period, strain the liquid off the fruit (I use a combination of colander, sieve and straining bag. Jellybags will do it, as will a teatowel if you’re careful). The thing to remember here is to recover as much liquid as possible but NOT to squeeze the fruit residue very hard. You’ll end up with a very cloudy liquid – this is as it should be.
Pour the liquid into a clean demijohn, top up to the shoulder with water (boiled and cooled if you want to, but I use it straight from the tap), put an airlock on, put the demijohn in a warmish place and wait.
You may get a very frothy fermentation (hence not topping up beyond the shoulder) or you may not. In any case, it will calm down. When it does, top up again to about a half-inch below the neck (it mustn’t touch the bottom of the airlock) and allow to ferement to a finish. You’ll know it’s finished when there are no more bubbles and a heavy sediment has fallen to the bottom of the demijohn.
At that point, pop back onto the site and scream for help in racking.
Piece of cake.
No guarantees, mind - I've never made it. But at least it's a simplified method and the recipe has every chance of being good.
Mike