How To Grow Yams

If you’re looking for a rewarding and productive crop, learning how to grow yams is a fantastic place to start. These starchy, nutritious tubers are a staple in many cuisines and, with the right approach, can be cultivated successfully in your own garden.

Yams are often confused with sweet potatoes, but they are a distinct plant from the genus Dioscorea. They thrive in warm, tropical to subtropical climates and require a long growing season. Don’t worry if your area has shorter summers—with some planning, you can still get a great harvest. This guide will walk you through everything, from choosing your planting material to storing your bounty.

Success with yams begins with understanding their basic needs. They are vigorous vines that need space, warmth, and well-drained soil to produce those large, edible tubers underground.

What You’ll Need to Get Started

Before you plant, gather your supplies. Having everything ready makes the process smooth and enjoyable.

Yam “Seed”: You don’t use true seeds. Instead, you plant small whole tubers or pieces called “setts” from a previous harvest.
Garden Space: A sunny spot with room for vines to run (at least 3-4 feet between plants).
Soil Amendments: Compost or well-rotted manure to enrich the soil.
Support Structure: A sturdy trellis, fence, or poles for the vines to climb.
Basic Tools: A shovel, hoe, and watering can or hose.

Choosing the Right Yam Variety

Select a variety suited to your climate and taste preferences. Some popular choices include:

White Yam (Dioscorea rotundata): The most common type, with white flesh and a rough, brown bark-like skin.
Yellow Yam (Dioscorea cayenensis): Has yellow flesh and often a longer, more cylindrical shape.
Chinese Yam (Dioscorea polystachya): Also called cinnamon vine, it’s more tolerant of cooler temperatures.

Always source your planting material from reputable nurseries or garden suppliers to avoid disease. Its important to start with healthy setts.

Preparing Your Garden Bed

Yams need loose, deep soil to form large tubers. Heavy clay soil will stunt their growth. Here’s how to prepare:

Choose a site that gets full sun for most of the day.
Loosen the soil to a depth of at least 12 inches. Break up any large clumps.
Mix in generous amounts of compost or aged manure. This improves drainage and provides nutrients.
Form mounds or ridges about 12 inches high. This further improves drainage and gives the tubers space to expand.

When to Plant Your Yams

Timing is crucial. Yams are extremely sensitive to frost and cold soil. Plant them 2-4 weeks after the last spring frost, when the soil has warmed up consistently. The soil temperature should be at least 70°F (21°C) for good sprouting.

Step-by-Step Planting Process

Now for the main event. Follow these steps to plant your yam setts correctly.

Prepare the Setts: If using large tubers, cut them into pieces weighing about 4-6 ounces. Each piece must have at least one “eye” or bud. Let the cut pieces dry in a shady, airy place for 1-2 days to form a callus over the cut surface. This prevents rot.
Plant the Setts: Place each sett on top of a prepared mound or ridge. Bury them just under the soil surface, about 2-3 inches deep, with the eye facing up.
Spacing: Space mounds 3 to 4 feet apart in rows that are 4 feet apart. The vines need plenty of room to spread.
Water Gently: After planting, give the area a thorough but gentle watering to settle the soil.

Caring for Your Growing Yams

Once planted, yams require consistent care throughout their long growing season, which can last 6 to 10 months.

Watering and Feeding

Yams need regular moisture, especially during dry spells, but they cannot tolerate soggy soil. Water deeply once a week if rain is lacking. Reduce watering as the tubers near maturity to improve their storage quality.

Feed your plants with a balanced, low-nitrogen fertilizer about a month after planting. To much nitrogen will encourage vine growth at the expense of tuber development. A side dressing of compost mid-season is also beneficial.

Training the Vines

Soon after sprouting, the vigorous vines will appear. Gently guide them onto your trellis or support. Training them upward saves space, improves air circulation, and makes pest monitoring easier. It also keeps the tubers cleaner and simpler to harvest.

Weeding and Mulching

Keep the area around the mounds weed-free, especially in the early stages. Weeds compete for nutrients and water. Applying a thick layer of organic mulch, like straw or wood chips, around the base of the plants helps suppress weeds, retain soil moisture, and keep the soil temperature even.

Common Pests and Problems

Yams are relatively hardy, but watch out for a few issues:

Root-Knot Nematodes: Microscopic worms that cause galls on roots. Rotate crops and use nematode-resistant varieties.
Yam Beetles: These insects chew on leaves and tubers. Hand-pick them off or use organic insecticides like neem oil.
Fungal Diseases: Like anthracnose, which causes leaf spots. Ensure good air circulation and avoid overhead watering to prevent fungal growth.
Rot: Caused by waterlogged soil. This is why well-drained soil and proper sett preparation are so critical.

Harvesting Your Yams

Harvest time comes in late autumn, after the vines have started to yellow and die back. This is usually just before the first frost in cooler areas.

Use a garden fork or spade, not a shovel, to minimize damage.
Start digging carefully from the side of the mound, well away from where you think the main tuber is.
Loosen the soil and gently lift the tuber out. They can be quite deep and large, so be patient to avoid bruising or cutting them.

Damaged yams will not store well and should be eaten first.

Curing and Storage Tips

Proper curing is essential for long-term storage. It heals minor wounds and toughens the skin.

Brush off excess soil gently—do not wash the yams.
Place them in a warm (80-85°F), humid, and well-ventilated spot for 10-14 days. A shaded porch or greenhouse often works well.
After curing, store the yams in a cool, dark, dry place with good air circulation. Ideal storage temperature is around 55-60°F.

When stored correctly, certain varieties of yams can last for several months. Check them periodically and remove any that show signs of spoilage.

FAQ: Your Yam Growing Questions Answered

Can I grow yams from a yam bought at the grocery store?

It’s possible but not recommended. Store-bought yams are often treated with sprout inhibitors and may not be a variety suited to your climate. They could also carry disease. It’s best to buy certified planting setts from a garden center.

What’s the difference between yams and sweet potatoes?

They are completely different plants. True yams (Dioscorea) have rough, scaly skin and starchy, often white or purple flesh. Sweet potatoes (Ipomoea batatas) have smoother skin and sweeter, moist flesh that can be orange, white, or purple. The terms are often misused in stores.

How long does it take to grow yams?

Yams require a long growing season, typically 6 to 10 months from planting to harvest. They are a commitment but a rewarding one.

Can I grow yams in containers?

You can, but it’s challenging due to the depth required for the tuber. You would need an extremely large, deep container (like a half-barrel) and a very vigorous trellis. For most gardeners, in-ground planting is more succesful.

Why are my yam vines not producing large tubers?

Several factors can cause this: soil that is too heavy or compacted, insufficient sunlight, overwatering, or too much nitrogen fertilizer. Ensure you’ve met the core requirements of loose soil, full sun, and proper feeding.

Growing yams is a test of patience that pays off handsomely. By following these steps—selecting good setts, preparing the soil properly, providing consistent care, and harvesting at the right time—you’ll be well on your way to enjoying your own homegrown yam harvest. The taste of a freshly dug yam from your garden is truly special.