A good merlot wine takes more than three months to make, which you should consider if you're making wine for a special occasion. Merlot has a strong flavor, so take into account your flavor preference when making your wine. For instance, blackberry juice gives the wine a neutral flavor.

Combine the potassium metabisulphate and 1 gallon of water in the bucket. Soak the cloth in the solution for five minutes, then use the cloth to clean the fermenters. (If you are planning on bottling your wine, you also will need wine bottling equipment, but that is outside the scope of this article.)

Combine the blackberry and merlot juices in one of the fermenters. Stir well.

Add yeast and Lalvin EC1118 champagne yeast on top. Let the mixture sit for 1 hour. Mix thoroughly.

Stir the mixture once per day for the next five days. Let sit for another two days.

Seal the fermenter, and let the mixture sit for 21 days.

Transfer the mixture into the second fermenter. Seal the fermenter, and let the mixture sit for another 28 days.

Bottle the wine per the instructions of the specific winemaking kit you purchase. Once you have bottled the merlot wine, let it stand for an additional 30 to 90 days.