Yams are excellent substitutes for potatoes. Growing this nutrient-high food can be a suitable task in most areas as long as the climate allows for an average of five months of warm temperatures. Growing yams in northern climates takes a bit more preparation and planning. Because yams like sandy soils with a great deal of space and warmth, it is necessary to put preparation into the pre-planting stage to give them the best chance to survive.
Prepare the soil for planting. Till the area with a rotary tiller, adding 6 inches of compost and working it into the soil. Raise the planting surface with the added compost to allow the plant more room to grow and offer better production and larger tubules. Begin the planting process in early May in northern climates to avoid the last frost.
Dig a hole for the cutting 1 foot deep. Trim all leaves from the cutting except for the upper most leaves, leaving the nodes on the stem. Plant the cutting with only the top-most leaves exposed. Bury the remainder of the cutting below the soil. Firm the soil around the cutting and dig a small reservoir around the base of the cutting. Space additional cuttings 12 to 18 inches apart and rows separated by 3 feet.
Spread mulch around the base of the cuttings and across the entire planting area 1 to 2 inches deep to protect against weeds.
Water cuttings regularly. Supply enough water to keep the soil moist. Do not over-water and leave the soil waterlogged as this will create root rot among the cuttings.
Protect the vines from any late season frost. Cover the vine with an old bed sheet or straw to prevent frost from forming on the vines if the nighttime temperature is going to drop below 50 degrees F. Uncover the next morning when the frost has disappeared.