Araru, scientifically known as Canna edulis, is a versatile plant recognized for its edible rhizomes, a primary source of starch. It has been cultivated for thousands of years as a staple food, particularly in indigenous cultures of South America.
Understanding Araru
Araru, also known as achira, Indian shot, or Queensland arrowroot, belongs to the Cannaceae family. This perennial plant typically grows up to 3 meters (9 feet) tall and 1 meter (3 feet) wide, featuring lush, bright green leaves 30 to 90 centimeters long. It produces showy flowers, often in shades of red, orange, or yellow. Its large, starchy rhizomes, which can be white, green, yellow-green, brown, or red-skinned, are the primary food source.
Native to South America, araru has been cultivated from Mexico to Brazil, especially in the Andean region, for 3,500 to 4,500 years. While both araru and Maranta arundinacea are sources of “arrowroot” starch, Canna edulis is a distinct species. Its starch granules are notably larger than those found in other common starch sources.
Cultivating Araru
Araru thrives in tropical to subtropical climates and tolerates high temperatures. While light frosts may damage foliage, underground rhizomes often survive, especially in USDA hardiness zones 7 to 10. For optimal growth and yield, araru requires at least six hours of full sunlight daily, though it can tolerate partial shade.
The plant adapts to various soil types, including sandy, loamy, and heavy clay, provided the soil is well-draining. A rich, humiferous soil with a neutral pH is preferred, but araru tolerates a pH range from 4.5 to 8. While it can withstand wet or even swampy conditions, well-drained soil generally yields better quality rhizomes.
Plant rhizomes in spring after the last frost, once soil temperature reaches at least 15°C (60°F). Plant them 10 to 15 centimeters (4 to 6 inches) deep, spacing them 30 to 60 centimeters (1 to 2 feet) apart for proper expansion. Each segment should have at least one or two visible buds. Araru requires consistent moisture during its active growing season, so regular watering is beneficial for good yields. Amending the soil with compost or manure and providing a balanced liquid feed monthly supports vigorous growth.
Araru is generally resilient to pests and diseases, but some issues can arise. Slugs may target young shoots, and common garden pests like aphids, spider mites, and leafrollers can affect foliage. Fungal diseases such as canna rust can also occur; manage this by removing infected leaves, ensuring adequate air circulation, and watering at soil level to keep foliage dry.
Harvesting and Processing Araru Starch
Araru rhizomes are typically ready for harvest six to twelve months after planting. For optimal yield, harvesting usually occurs eight to ten months into the growing cycle. In consistently warm climates, rhizomes can be harvested year-round as needed. Harvest rhizomes before the plant flowers for best quality. Once harvested, process them quickly due to their perishable nature.
Extracting araru starch involves several steps. Cleaned rhizomes are grated into a fine pulp, then washed with water to separate starch granules from fibrous material. The large starch granules quickly settle. After settling, the water is decanted, and the wet starch is collected. This wet starch is then spread out to dry, often in the sun, resulting in a fine, white powder.
Uses and Benefits of Araru
Araru rhizomes can be consumed raw, boiled, baked, or steamed. Its starch serves as an excellent thickening agent, used in soups, sauces, and desserts. Flour from araru starch is also used in traditional breads, pastries, biscuits, and to produce cellophane noodles in some Asian cuisines. Beyond the rhizomes, young shoots and leaves are edible and can be cooked as a nutritious green vegetable.
Nutritionally, araru rhizomes are rich in starch, typically containing about 24-25% by fresh weight and 75-80% on a dry matter basis. The flour is naturally gluten-free and easily digestible. It provides vitamins A, B1, B2, B3, B6, and C, along with high potassium content. While rhizomes contain 1-3% protein, young shoots and leaves offer about 10%. Traditionally, araru has been used to address digestive issues, as a soothing agent, and is reported to have diuretic and analgesic properties; its leaves and rhizomes are also used as fodder for livestock.