Plant Merlot grapevines in the spring, after the threat of the frost has passed. Weed the area carefully and separate plants by at least 18 inches.
Mulch around the base of the vines at the beginning of every spring. Water heavily whenever the mulch is dry all the way to the soil.
Prune any dead leaves and shoots whenever they appear. Cut the dead sections off down to the nearest separation, even if it means trimming away some live material.
Prune back the vines a few weeks after the harvest, while the vine is dormant but before the weather freezes. Cut away all but 15 to 18 shoots on every 3 feet of vine trunk.
Prune off excess buds from each shoot. Shoots larger than a thumb should contain three buds, two if it is the size of a middle finger and only one if it is the size of a pinky or smaller.
Pound a wooden pole into the ground with a sledgehammer near the base of the plant. Place it as close to the plant as possible without damaging the roots.
Harvest grapes in mid-summer for a wine with higher acidity and in late-summer for a fuller-bodied wine. Examine the fruit for skin rot, and discard any bad foot to prevent spreading.