Also known as yam bean, Mexican potato, and Mexican turnip, jicama requires roughly nine months of hot weather to produce a healthy crop. Thankfully, this requirement can be managed in colder regions by starting seeds indoors before warm weather is consistent (and a greenhouse doesn’t hurt, either). Just be careful to plant your jicama in a place securely away from children and pets, as the skin, stems, seeds, and leaves are toxic—so only the vegetable’s flesh is safe to eat. However, if you’re feeling adventurous enough to try something new in the garden, jicama might just be the plant you’re looking for. Jicama plants can grow in the ground or in containers, so either option is suitable depending on the space in your garden. An area with full sun is ideal. Similar to growing potatoes, jicama can grow in rows outdoors that are spaced about one foot apart (using the same distance between each seed, or at least 8 inches). The same spacing can be used for plants in containers, and the seeds should be planted about half an inch deep.
Jicama Plant Care
Light
Jicama prefers full sun. This species is a day-length sensitive plant, which means that the tubers are not produced until the days toward the end of the growing season are fewer than nine hours long. Jicama can also be grown indoors under a light set-up; even if gardeners can only grow one or two plants, they can still produce a harvest. Cloches can be used outdoors at the beginning of the season to hasten the process in the early stages and to acclimate the young plants to the outdoors.
Soil
Jicama grows best in well-drained soil that is loamy and sandy. It can be planted outside once hardened off, or seeds can be planted directly outside in USDA Hardiness Zones 10 through 12. If the soil is rich with organic matter, light, and friable, gardeners may only need up to four months for smaller roots to mature (which are equally as tasty as large plants). Similar to potatoes, any parts of jicama growing above soil level are toxic, so it’s important to avoid eating any parts that were growing above the soil level. If you see any parts of the tubers being exposed to the sun, cover them with soil similar to the process of growing potatoes.
Water
Jicama does not tolerate soggy soil, but it does require consistent waterings that prevent the soil from drying out. Water the plant at the soil line rather than on the leaves. Ensure your jicama plants receive at least 2 inches of water per week to mature and produce healthy tubers.
Temperature and Humidity
Jicama plants are very sensitive to frost, and they don’t tolerate temperatures below 50 degrees. Outside, your plants will thrive in hot weather with average to high humidity levels. If you have a short, cool growing season, jicama can also be grown in polyethylene tunnels or greenhouses. These will heat up the environment surrounding the plants with the added bonus of keeping pests at bay. Shorter days at the end of the growing season often coincide with the first frosts of fall, so you may need to provide protection to get tubers of a usable size. If you don’t have a greenhouse or polyethylene tunnel, cloches and portable cold frames can protect the foliage from the threat of frost while warming the micro-environment around the plant itself, thus extending the season.
Fertilizer
Since the part of jicama plants used by humans is in the ground, it’s best to avoid high-nitrogen fertilizers that boost leaf and stem growth. Instead, encourage root growth by using a potassium-rich fertilizer about once per month during the growing season. For the amount to use, follow the product label instructions.
Pollination
Jicama plants are self-pollinating, meaning the flowers contain both male and female parts required for pollination. This species is also pollinated by insects when grown outdoors, but gardeners do not need to hand-pollinate jicama plants.
Types of Jicama
Jicama vs. Potato
While the two plants share many similarities, jicama and potatoes also have considerable differences. Jicama is sweeter in taste, larger, and it also has a crispier texture. This vegetable has a round appearance in comparison to the potato’s oval or long, thin varieties.
Harvesting Jicama
After a long growing season, your jicama plants are ready to harvest once the foliage has died off, or just before the first frost of fall. Stop watering the plants a few weeks before harvesting to begin the curing process. Allow plenty of time for the tubers to develop by harvesting jicama late in the season, but try to harvest before they’ve reached more than 6 inches in diameter for a softer, tastier vegetable. Dig the tubers out of the soil and completely remove the vine. Once harvested, store your jicama in a cool, dark location (between 50 and 60 degrees) to prevent it from getting woody and tough. The vegetables can be stored for up to two months. When you’re ready to eat, simply rinse your jicama off and peel the skin. Remember that along with the foliage of this plant, the skin of jicama’s tubers is also toxic, so it’s essential to remove all skin before consumption.
How to Grow Jicama in Pots
If you don’t have space in the garden, jicama can also be grown in pots. This is a great way to isolate your jicama plants from children and pets, or simply to save space for other vegetables in your garden. Choose a location that receives full sun. Use a pot that provides plenty of drainage, keeping in mind that jicama needs consistently wet (but not soggy) soil to thrive. Plastic, glazed ceramic, and terracotta pots are all great options. Terracotta, in particular, allows excess water to evaporate easier. The plants will require support at some stage if you want to keep them off of the ground. You can train jicama on a net, wire fence, or bamboo tripod, but remember that if it is raised off of the ground, it might be more difficult to protect it from frost. Greenhouses are the best option to grow jicama in containers and keep adequate temperatures (above 50 degrees).
Pruning
When it comes to pruning, your jicama plants will need consistent pruning while they’re flowering. To encourage bushy, dense growth, pinch out the growth tips once the plants are getting too big. Do not let the plants go to seed; pinch the flowers for added root production. Deadheading flowers can significantly increase the root harvest each fall, as this prevents the plants from expending valuable growing energy on flowers rather than roots.
Propagating
Since jicama is a root vegetable, it can’t be propagated by stem cuttings or rooting stems in water. Instead, after harvesting the tubers from your first jicama plant, you can save tubers for propagation next season. Planting a whole jicama tuber also decreases the time needed to grow it to maturity, so this is a great option for gardeners to continue growing jicama year after year without purchasing new seeds. You can also allow one jicama plant to go to seed (skip deadheading the flowers) and save these seeds to plant the following year. Simply remove the seeds from your plant and save them in a cool, dry location similar to storing tubers, then start them in soil when the growing season returns.
How to Grow Jicama From Seed
To grow jicama from seed, you can either place the seeds directly in the ground or start them in containers indoors. Soak jicama seeds in water overnight before either planting option. When growing jicama in the ground, plant the seeds about half an inch deep in rows spaced about one foot apart with at least 8 inches between each seed. To plant jicama seeds in containers after soaking them overnight, sow at least two seeds in a 4-inch container filled with a potting mixture intended for seedlings. Place them under a grow light, on a warm windowsill, or in a greenhouse. Start seeds indoors approximately 8 to 10 weeks before the last frost date (or earlier if your region’s growing season is limited due to long winters). Thin the seedlings once germination is complete, leaving the strongest seedling in each pot to thrive.
Potting and Repotting
If you live in a cold region, it’s recommended to grow young jicama plants indoors before transplanting them outside in the spring. When growing jicama in containers throughout the season, your plants will also need to be transplanted into larger pots regularly as they outgrow their current containers. Gently remove your jicama from its container. If your plants are quite large, it may be helpful to recruit a friend to help you lift the plant and its buried tubers carefully. Place it inside its new pot, then add plenty of soil to cover the tubers entirely. Water the plants regularly for at least one week to ensure the soil doesn’t dry out, then care for them as usual.
Overwintering
Jicama plants will not survive outdoors during the winter, however, most gardeners have harvested their vegetables before the first frost of fall. Overwinter your harvest (along with any saved seeds) in a cool, dry place with temperatures between 50 and 60 degrees. In the spring, seeds and tubers can be replanted to grow new jicama plants.
Common Pests and Plant Diseases
Jicama’s stems, leaves, and flowers are toxic, which keeps most pests at bay naturally. Most gardeners won’t encounter any pest infestations when growing jicama. However, this species is still susceptible to weevils and plant diseases. Your jicama plants may experience root rot when overwatered, so it’s essential to prevent the soil from becoming oversaturated with water. Use pots with proper drainage when growing jicama in containers, and keep a consistent watering schedule (2 inches per week) for jicama in the garden.
