Native peoples of Tropical America have cultivated and eaten jicama (Pachyrrhizus erosus) for generations. The turnip-like root tubers with sweet woody flavors have become a modern-day delicacy for chefs and food-lovers worldwide. Having a long growing season of at least four months, fertile, organic-rich soil that is moist and warm and sunlight are the basic requirements for growing jicama in your home garden.
Soak seeds of jicama in lukewarm water for 24 hours. Seeds need only be covered in shallow water to loosen the hard seed coat, making germination faster and more likely.
Sow seeds outdoors when there is no danger of frost. Poke a small hole about 1/4 to 1/3 inch into a loose, fertile soil that is rich in compost. A sandy soil with organic matter is ideal as long as it is moist and very soggy. Place the seed in the hole and cover the seed with soil, lightly tamping the soil down to bring the seed in direct contact with soil.
Gently sprinkle water over the planted seeds so the soil is moist. Monitor the area for several days, watering only when the soil becomes slightly dry to the touch. The warmer the weather and soil temperatures, the faster the plants will germinate and sprout from the ground.
Allow the vine-like stems to grow as a billowy groundcover or upon a short trellis or plant stakes. When the stems' length approaches 36 inches, expect pea-like flowers to appear. Enjoy them, but as soon as they fade, pinch them off to prevent seed pods from forming. Removing the pods refocuses energy into producing larger root tubers.
Harvest the root tubers from the soil no sooner than 4 months of plant growth, when they will be small but edible-sized. Dig up the tubers with a shovel, slicing into the ground no closer than 12 inches at first to avoid damaging a tuber. Make more digs under the plant as more tubers are revealed. If climate allows, waiting to harvest after 8 to 9 months of growth ensures larger roots. Always harvest the tubers when threats of a killing first fall frost are expected.
Brush off soil from the lifted tubers, gently washing or soaking them in water to remove attached mud clumps. Allow the tubers to air dry fully before storing in a cool dry location, between 50 and 65 degrees F, before using them in a culinary recipe.