Give your plums a good wash in water, discarding any that are overly bruised or moldy. Add them to a sterilized fermentation bucket, and bash them up quite a bit with a potato masher or a (clean) wine bottle. I like to keep the pits in because it gives the wine a really nice almond flavor.
Bring your gallon of water to the boil, and pour over your crushed plums. Put the lid on your bucket, and leave it for a few days (3-4) and swirl it around every day.
Add the lemon juice and sugar to your fermenting plums, and stir to mix. Then sprinkle the yeast on top. After an hour or so, give it a good stir. Cover and leave someplace warm for four days, stirring once or twice a day. (Sometimes I just grab the bucket and firmly swish it around.)
It’s time to move it to some demijohns. I like to do this by just using a siphon hose in the bucket, with a funnel topped with a small sieve in the mouth of the demijohn. Keep the hose a good inch away from the bottom of the bucket, so you don’t suck up all of the yeasty sediment. Once you have the wine in the demijohn(s) top with an airlock.
After two weeks, rack the wine by siphoning into newly sterilized demijohns, being careful to leaf the sediment in the bottom of the old ones.
Taste it after three weeks, and see how you like it. We basically started bottling some of it at this stage, leaving the rest to age and racking again over the next couple of weeks. It is ALL good! The longer you wait to drink it, the drier and more clear it becomes, so it’s really up to you. I just finished bottling the last of it, about six weeks after starting it.
If you are not planning on drinking it quickly, then leave it in the demijohn longer. What you don’t want is a lot of young, active wine in bottles for a long period of time. They could keep fermenting and build up too much carbonation. So, if you’re in it for the long haul, just keep it in the demijohns for a few months, racking monthly, before bottling. But you can definitely drink this wine young, as we have.