Some years ago I planted 4 rhubarb plants. One died, one kept producing seeds and few stalks and the other 2 gave me enough to make a gallon of very good wine before one died and the other became under productive. Part of the problem was that they were planted too closely but there was also competition from persistent weeds. So this year I made a fresh start, digging out all the weeds, digging in lots of compost and chicken manure, then covering with weed control fabric topped with bark chips. I put in 6 plants, 1 metre apart and kept them watered. Months later, I now have 6 really big healthy plants. Some say not to harvest the first year and that end of season rhubarb is no good.
I ignored all that and took 3.5 kilos. I sliced the stalks and put them through my fruit crusher. They were tough and crushing produced very little juice so I covered them with a kilo of sugar along with rohavin and pectolytic enzymes and left for 24 hours. Next day I put the whole lot through the fruit press twice and got 2.5 litres of juice with excellent flavour and aroma. With a pH of 4.4, the acidity was surprisingly low, so I added tartaric acid to adjust this to 3.7 plus 200 ml of white grape juice concentrate, yeast, nutrient and water to 5 litres, with sg 1090. So far so good.