Taro, scientifically known as Colocasia esculenta, is a tropical perennial plant cultivated primarily for its starchy underground stem, or corm, which is a staple food in many regions around the world. This crop, also referred to as dasheen or eddo, originated in Southeast Asia and remains an important source of carbohydrates. Successful cultivation requires careful attention to the plant’s specific environmental needs and a systematic approach from preparing the soil to handling the final harvest.
Essential Environmental Requirements
Taro thrives best in tropical and subtropical regions where temperatures are consistently warm, with an optimal daily range between 21 and 27 degrees Celsius. The plant requires high humidity and a long growing season, needing at least 200 frost-free days to fully mature its corms. Taro generally needs ample sunlight to maximize its yield, though some varieties tolerate partial shade.
The soil conditions favor deep, fertile, loamy, or sandy loam soil that is rich in organic matter. A slightly acidic to neutral pH level, ideally between 5.5 and 7.5, helps ensure efficient nutrient uptake. Taro requires consistently moist conditions, but the specific cultivation method determines the water regime, distinguishing between dryland (upland) and wetland (paddy) systems.
Preparing and Planting the Taro Crop
Land preparation begins by clearing the area of weeds and debris, followed by deep plowing or tilling the soil to a depth of 8 to 10 inches for good aeration. Organic matter, such as well-rotted manure or compost, is incorporated into the soil to enhance fertility and improve moisture retention. For dryland cultivation, the soil is often shaped into raised beds or ridges to facilitate drainage and prevent waterlogging.
Propagation is achieved vegetatively, most commonly using small corms, cormels, or suckers. These planting materials are placed in the prepared soil at the beginning of the rainy season. The material is typically planted deep, around 15 centimeters, to allow sufficient space for the corm to grow downward. Spacing is relatively wide, often 80 to 100 centimeters between plants, to give each individual adequate room for development.
Cultivation and Maintenance During Growth
Water management is the most demanding aspect of taro cultivation, as the plant cannot tolerate dry conditions for extended periods. Upland taro requires frequent irrigation to keep the soil consistently moist, but not saturated. Wetland taro is grown in flooded paddies with standing water. Wilting in the leaves indicates a need for immediate watering to prevent stress that can severely reduce the final corm yield.
Taro requires a robust fertilization schedule to support the growth of its large leaves and starchy corm. Applications of balanced fertilizer, particularly those rich in nitrogen and potassium, are required periodically throughout the active growth phase. Potassium is important for proper corm bulking and starch development.
Weed control is a continuous process because taro is sensitive to competition for nutrients and light, especially when young. Manual or mechanical weeding is often preferred over chemical herbicides due to the plant’s sensitivity. Growers must also monitor for diseases like taro leaf blight, caused by Phytophthora colocasiae, which can rapidly destroy foliage. This necessitates the use of disease-resistant varieties or fungicidal treatments. The typical growth cycle usually requires between 6 and 18 months for the corms to reach full maturity.
Harvesting and Post-Harvest Handling
The readiness of the taro corm for harvest is signaled by the natural senescence of the foliage, where the large, heart-shaped leaves begin to turn yellow and die back. Harvesting is usually done by hand, carefully digging or pulling the entire plant to avoid damage to the main corm and any attached cormels. Care must be taken, as physical injuries to the corm can serve as entry points for pathogens.
Once harvested, the corms benefit from curing, a brief period of drying to allow minor surface wounds to heal. Curing is best performed in a shaded, well-ventilated area at a warm temperature, typically between 20 and 30 degrees Celsius, for a few days. This healing process reduces moisture loss and extends the storage life of the corms. For longer storage, taro should be kept in a cool, dry, and well-ventilated environment, ideally between 7 and 10 degrees Celsius.