By Kristine Adel
If you’ve ever dug up potatoes with dirt under your nails and sunshine on your back, you already understand the magic of tubers. These underground storage organs have fed civilizations, survived famines, inspired exploration, and continue to be some of the easiest and most satisfying crops for home gardeners to grow.
What Is a Tuber?
A tuber is a swollen underground plant structure that stores nutrients and energy. Unlike roots, tubers contain buds or “eyes” capable of growing into new plants.
The most familiar example? The humble potato. But tubers come in many forms, flavors, and colors.
Common Tubers you may already be familiar with include:
Potatoes
The classic tuber crop. Potatoes originated in the Andes Mountains of South America and became one of the world’s most important food sources.
Popular varieties for Virginia gardens include:
Yukon Gold
Red Pontiac
Kennebec
Purple Majesty
German Butterball
Sweet Potatoes
Technically a tuberous root rather than a true tuber, but often grouped together in gardening discussions.
Sweet potatoes thrive in warm summers and do very well in southern Virginia.
Favorites include:
Beauregard
Georgia Jet
Covington
Jerusalem Artichokes (Sunchokes)
These sunflower relatives produce knobby edible tubers with a nutty flavor. Extremely hardy and productive — sometimes too productive.
Dahlias
Though grown mostly for flowers, dahlias form tubers underground that can be divided and replanted each year.
Yams
True yams are tropical and less common in American gardens, though they are staple foods in many African and Caribbean cultures.
A Brief History of Tubers
Tubers changed human history. Potatoes were first cultivated over 7,000 years ago in Peru and Bolivia. Spanish explorers brought them to Europe in the 1500s, where they gradually became essential food crops for many reasons. They produce heavily in small spaces. They store well. They provide excellent nutrition.
The Irish Potato Famine of the 1840s showed both the importance — and danger — of relying too heavily on a single crop variety. Today, there are thousands of varieties to choose from.
Sweet potatoes have an equally fascinating history, traveling across the Pacific, through Polynesia and the Americas long before modern global trade routes developed.
Today, tubers remain some of the world’s most important staple foods.
Best Growing Conditions
Tubers generally prefer:
loose, well-drained soil,
consistent moisture,
full sun,
and good airflow
Heavy clay soil can cause misshapen tubers or rot. Raised beds or amended soil help tremendously.
Planting Potatoes
Plant seed potatoes in early spring, typically March through early April.
Soil temperatures should ideally be above 45°F.
Cut seed potatoes into chunks with at least one “eye” each and allow them to dry for a day before planting.
Plant 4–6 inches deep, 12 inches apart, in rows about 2–3 feet apart.
Hilling
As potato plants grow, mound soil around the stems (“hilling”). This prevents the potatoes from greening and increases yield.
Sweet Potato Slips and Tips
Sweet potatoes love heat. Plant slips (young plants) after danger of frost passes. Mulch can be used to warm your soil early. Do not cut, dry, and plant sweet potato tubers the same as ordinary white potatoes. They won’t grow nearly as many new tubers as slips can produce.
Slips
To grow your own potato slips, set a sweet potato in a tray on top of a layer of dirt, in a warm sunny place. Wait for the potato to grow new shoots. Twist and pinch the new shoots (slips) at the base, and put them into à glass of water to develop roots. When the roots have developed, plant them in small pots to grow until the weather and the soil are above 65° to 70°. Then transplant them into your garden. Harvest before the first hard frost in October.
Storage
Proper curing and storage can dramatically extend shelf life.
Store white potatoes in cool, dark, humid conditions. Avoid refrigeration, which converts starches into sugars.
Sweet Potatoes need to be cured before storing. Curing sweetens the vegetables and toughens the skins. To cure, leave the sweet potatoes in a consistently warm place like an upstairs room or warm attic, approximately 80–85°F for about 7–10 days. Then wrap in brown paper and store in a cool, dry, and dark place until needed.
Fun Tuber Facts
White potatoes, sweet potatoes and yams are not biologically related to one another. Potatoes, from the plant family Solanaceae, are related to tomatoes and peppers. Sweet potatoes, from the plant family Convolvulaceae, are related to morning glories. And, yams, which belong to the Dioscoreaceae plant family, are related to grasses and lilies.
One potato plant can yield 5–10 potatoes or more.
Purple potatoes contain antioxidants similar to blueberries.
Dahlias were once grown as food crops.
Tubers truly are underground garden treasures. They rest underground through darkness and cold, storing life quietly until conditions are right to emerge again. Another reminder that growth often begins unseen.
Happy digging!
Don’t forget to tune into WHEO Tuesday morning May 26, 8:30 to 9 a.m. with Patrick County Master Gardeners for more on Potatoes and Tubers. Find us on Facebook or contact us at https://patrickmastergardeners.org/.
