Pachyrhizus erosus Seeds | Jicama

Jicama (Pachyrhizus erosus) climbing vine with trifoliate leaves, blue flowers and the large crisp tuber beside it — Jicama (*Pachyrhizus erosus*): Fabaceae, the Mexican yam bean grown for its crisp, sweet root.

LATIN NAME: Pachyrhizus erosus

COMMON NAME: Jicama, Mexican Yam Bean

Plant Profile

Jicama is a fast-growing climbing legume from Mexico and Central America, twining four to five metres over any support with trifoliate leaves and clusters of blue-and-white pea flowers in late summer. Beneath the soil the plant’s work sits: one large, turnip-shaped tuber, crisp as an apple and sweet as a water chestnut.

It is a plant of the warm season, needing a long, hot growing season to size the root, and it fixes nitrogen like the rest of its family. The vine dies back at first frost, and the root must be harvested before the ground chills. The tuber can weigh several kilos in a long-season climate, its skin papery tan and its flesh white and astonishingly crisp for a root crop.

Science & Biotechnology

The crop’s botany carries a hard warning: every part above ground, especially the seeds, contains rotenone and related toxic compounds, and only the tuber is food, a fact documented in food-safety literature and drilled into every gardener who grows it.

Agronomic research has examined the crop’s tuber chemistry, its inulin-type carbohydrates valued for a low-calorie sweetness, and its role in traditional milpa systems where it grows alongside maize and beans. Studies of the crop’s milpa companionship document how the vine and maize share the same support, an old polyculture the modern literature keeps finding new in. Post-harvest studies show the tuber stores best unwashed in cool darkness, which is why market vendors keep the dirt on until the point of sale.

Uses & Benefits

In the kitchen the peeled root is the thing: julienned into salads, eaten raw with lime and chilli, or cooked briefly, holding its crunch where other vegetables would go soft. It stores for months in cool, dry conditions.

In the garden the vine covers a fence through summer and improves the soil as it climbs, a legume that pays two ways for the space it takes. In Mexico the root is sold peeled in sticks by street vendors, spritzed with lime and chilli, the everyday way the world eats this crop.

Growing from Seed

Scarify the hard seeds and soak them overnight, then sow an inch deep into a warm, free-draining mix; the seedlings emerge within a week in soil above twenty degrees.

Give the vines a strong trellis in full sun, water steadily, and pinch the flower buds to push energy into the tuber; harvest before any frost touches the ground, cutting the vine and lifting the root whole. Start the seed in warmth four to six weeks before the last frost, since the long-season requirement is the crop’s one demand and every warm week counts. Mulch the root zone deeply once the vines are established; the tuber sits close to the surface and dislikes a hot, dry crown in midsummer.

Our Take

The apple-crunch root of Mexican markets, climbing a trellis through summer. Warmth, a support, and the discipline to eat only what grows underground.

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