How to grow jicama
Overview
Jicama (Pachyrhizus erosus) is a warm-season legume grown for its crisp, sweet tubers that resemble a cross between an apple and a water chestnut. The plant produces vigorous vines and requires a long, hot growing season of at least 5–6 months to develop sizeable roots.
Varieties
- Mexican — The standard commercial variety with large, round tubers and good flavour.
Soil Preparation
Jicama prefers a loose, well-drained loam with a pH of 6.0–7.0. Before planting, dig in 2–3 cm of well-rotted compost or aged manure to improve fertility and moisture retention. Avoid heavy clay or waterlogged soils, which can cause root rot.
Growing Guide
Plant jicama in a position with full sun and well-drained, fertile soil. Sow seeds 2–3 cm deep, 30 cm apart, in rows 60–90 cm apart after all frost risk has passed and soil is consistently warm. Provide a sturdy trellis or fence for the vines to climb, as this improves air circulation and pod set. In cooler temperate zones, start seeds indoors 4–6 weeks before the last frost to extend the season.
Sowing
Sow jicama seeds directly into warm soil after frost danger has passed, at a depth of 2–3 cm. Space seeds 30 cm apart in rows 60–90 cm apart. Germination takes 7–14 days in soil temperatures above 20°C. In cooler zones, start seeds in pots 4–6 weeks before transplanting.
Care
Feed jicama every 4–6 weeks with a balanced fertiliser (e.g., 10-10-10) during active growth. Train the main vine onto a trellis and prune side shoots to improve airflow. Remove yellowing or diseased leaves promptly to reduce fungal pressure.
Companion Planting
Jicama grows well with sweet corn, which provides a natural climbing support, and with other warm-season legumes like cowpea. Avoid planting near potatoes or other root crops that compete for underground space and may be harvested at different times.
Common Pests & Risks
Bean beetles (leaf beetles) may chew leaves and pods; handpick or use a fine insect netting. Aphids and whitefly can appear on new growth; blast off with water or apply a soft soap spray. Root-knot nematodes can cause stunted growth in sandy soils; rotate crops and amend soil with organic matter.
Harvesting
Harvest jicama tubers when the vines begin to yellow and die back, typically 5–6 months after sowing, before the first winter frost. Dig carefully with a garden fork to avoid damaging the roots; the tuber is ready when it is 10–15 cm in diameter and feels firm. Store harvested jicama in a cool, dry place for several weeks.
In the Kitchen
Jicama tubers are eaten raw, peeled, and sliced into salads or crudités for a crisp, slightly sweet crunch. They can also be stir-fried or added to soups. Store unpeeled tubers in a cool, dark place for up to 2 weeks; once cut, refrigerate in water.
Troubleshooting
Yellow leaves: often caused by overwatering or poor drainage; reduce watering and improve soil. Brown leaf edges: indicates potassium deficiency; apply a potassium-rich fertiliser. Small tubers: result from a short growing season or cool weather; ensure a long, hot summer and start early. Vines not flowering: may be due to too much nitrogen; switch to a low-nitrogen fertiliser. Pods dropping: can be from inconsistent moisture; maintain even soil moisture.