Jicama from Seed: Trellis Setup, Harvest Window & Prep Basics
Answer: Jicama is grown from seed, not tubers, and needs a long, warm season to develop its edible root. A sturdy trellis helps manage the vine, and harvest typically happens before the first frost, when vines start to die back. After digging, let the tubers dry and brush off soil before storing or using.
Why Grow Jicama from Seed
Jicama (Pachyrrhizus erosus) is a tropical legume grown for its crisp, juicy tuber. Unlike potatoes or yams, you can’t just cut up a jicama and plant the pieces. It must be grown from seed, usually sown indoors well before the last frost or directly in warm climates.
Many gardeners start jicama seeds indoors because the plant needs a long growing season—often around 150 days or more to produce a decent-sized root. Starting early gives you a better chance of harvest before cold weather hits.
Starting Jicama Seeds
Seed Prep: Soak and Sprout
Jicama seeds are large and can be slow to germinate. To speed things up, many people soak them in room-temperature water for several hours or overnight before planting. Some even wrap them in a damp paper towel inside a loose plastic bag and keep them warm until a small white root appears.
Optimal soil temperature for germination is between 70–85°F (about 21–29°C). At these temps, seeds may sprout in 10–21 days, though some take longer depending on conditions.
Sowing: Indoors vs. Outdoors
In most temperate zones, it’s best to start jicama indoors 12–14 weeks before the last expected frost. Use small pots or cells filled with a light, well-draining mix. Sow seeds about 1 inch deep and keep the soil consistently moist but not soggy.
Direct sowing outdoors is usually only practical in very warm, long-season climates where soil stays reliably warm. If you do sow outside, choose a spot with full sun and loose, well-drained soil.
Transplanting Seedlings
Once seedlings have a few true leaves and outdoor temperatures are reliably warm (especially soil), they can be transplanted. Harden them off first to reduce shock.
Space plants about 12 inches apart in the garden or one per 7-gallon container if growing in pots. Jicama is a vigorous vine, so give it room to spread or climb.
Trellis Setup for Jicama
Why Trellis Jicama
Jicama grows into a fast, sprawling vine that can easily cover several square feet. Trellising helps keep the plant off the ground, improves air circulation, and makes it easier to manage in a small space or raised bed.
A trellis also keeps the developing tuber area less crowded, which may help with root development in some gardeners’ experience, though the tuber itself grows underground.
Simple Trellis Options
A basic trellis can be as simple as a sturdy stake, a tomato cage, or a small A-frame made from bamboo or metal. For multiple plants, a taller trellis (4–6 feet or more) works well.
Secure the trellis firmly in the soil or container so it can support the weight of the vine as it grows. Gently guide the main stem to the support and loosely tie it if needed.
Training the Vine
As the vine grows, you can train it up the trellis by loosely tying or weaving it through the structure. Many people pinch off excess side shoots or keep the vine pruned to 3–5 feet to focus energy on the root.
Flowers and seed pods are normal, but if you’re after a larger tuber, consider pinching off flowers so the plant puts more energy into the root rather than seeds.
Harvest Window: When to Pull Jicama
Timing the Harvest
Jicama is typically ready to harvest around 150 days after planting, or just before the first frost in your area. In frost-free zones, some gardeners leave plants in the ground longer, as long as soil doesn’t freeze.
A good sign that it’s time to harvest is when the vines start to yellow and die back. If you’re saving seeds, you may wait until seed pods have fully browned and dried.
How to Harvest Jicama
To harvest, carefully dig around the base of the plant with a fork or trowel. The tuber grows underground, usually 3–6 inches in diameter, but size can vary.
Work gently to avoid cutting or bruising the root. Follow each vine back to its tuber and lift it out by hand if possible. Cut the vine above the tuber once it’s free.
How Many Tubers per Plant
Most jicama plants produce one main tuber, though occasionally a plant may form two smaller ones. Spacing plants about 12 inches apart gives each enough room to develop a decent-sized root.
Post-Harvest Prep and Storage
Cleaning and Drying
After harvest, let the tubers sit in a dry, shaded spot for a short time to let excess soil dry. Then brush off dirt with a soft brush or cloth—no need to wash them yet.
Washing right away can shorten storage life, so many people wait until just before using.
Storage Conditions
Jicama is sensitive to cold and can be damaged if stored below about 50°F. Ideal storage is in a cool, dry place around 53–60°F, such as a heated basement or garage.
When stored properly, jicama may keep for up to two months, though exact shelf life depends on conditions and variety.
Kitchen Prep Basics
In the kitchen, jicama is peeled before eating. The skin is tough and inedible, but the flesh inside is crisp and slightly sweet.
Cut the tuber into sticks, cubes, or slices as needed. It’s great raw in salads, slaws, or as a crunchy snack with lime and chili. Cooked, it can be stir-fried or roasted, though many people prefer it raw.
Key Terms
- Tuber: The edible underground storage organ of the jicama plant.
- Photoperiod: The length of daylight, which can influence tuber formation in some tropical root crops.
- Hardening off: The process of gradually acclimating indoor-grown seedlings to outdoor conditions.
- Perennial (in tropics): Jicama is a perennial in frost-free regions but grown as an annual in temperate zones.
- Legume: Jicama is a member of the bean family; its seeds are toxic and should not be eaten.
Safety Notes
The vine, leaves, and seeds of the jicama plant contain rotenone and other compounds that are toxic if eaten. These parts should not be consumed, though handling the plant and seeds is generally safe with normal precautions.
“Jicama is a legume, and like many legumes, the seeds and foliage are poisonous. Only the tuberous root is edible.”
— Dr. Joe Masabni, Extension Horticulturist, Jicima – Texas A&M AgriLife Extension
Leave a comment