Siam Villa Garden: Sacred Lotus

Nelumbo nucifera, also known as Indian lotus, sacred lotus, or simply lotus, is one of two extant species of aquatic plant in the family Nelumbonaceae. It is sometimes colloquially called a water lily, though this more often refers to members of the family Nymphaeaceae.

Lotus plants are adapted to grow in the flood plains of slow-moving rivers and delta areas. Stands of lotus drop hundreds of thousands of seeds every year to the bottom of the pond. While some sprout immediately, and most are eaten by wildlife, the remaining seeds can remain dormant for an extensive period of time as the pond silts in and dries out. During flood conditions, sediments containing these seeds are broken open, and the dormant seeds rehydrate and begin a new lotus colony.

Under favorable circumstances, the seeds of this aquatic perennial may remain viable for many years, with the oldest recorded lotus germination being from seeds 1,300 years old recovered from a dry lakebed in northeastern China. Therefore, the Chinese regard the plant as a symbol of longevity.

It has a very wide native distribution, ranging from central and northern India (at altitudes up to 1,400 m or 4,600 ft in the southern Himalayas[4]), through northern Indochina and East Asia (north to the Amur region; the Russian populations have sometimes been referred to as "Nelumbo komarovii"), with isolated locations at the Caspian Sea. Today the species also occurs in southern India, Sri Lanka, virtually all of Southeast Asia, New Guinea and northern and eastern Australia, but this is probably the result of human translocations. It has a very long history (c. 3,000 years) of being cultivated for its edible seeds, and it is commonly cultivated in water gardens. It is the national flower of India and Vietnam.

The Sacred Lotus grows in water up to 2.5 m (8 ft) deep. The minimum water depth is about 30 cm (12 in). In colder climates, such a low water level, which heats up more quickly, is helpful for better growth and flowering. Lotus germinates at temperatures above 13 °C (55 °F). Most varieties are not cold-hardy. In the growing season from April to September (northern hemisphere), the average daytime temperature needed is 23 to 27 °C (73 to 81 °F). In regions with low light levels in winter, the sacred lotus has a period of dormancy. The tubers are not cold resistant, but can resist temperatures below 0 °C (32 °F) if they are covered with an insulating cover of water or soil. During winter time, the roots have to be stored at a frost free place.

The rhizomes of lotus (Chinese: 蓮藕 lián-ǒu) are consumed as a vegetable in Asian countries, extensively in China, Japan, and India: sold whole or in cut pieces, fresh, frozen, or canned. They are fried or cooked mostly in soups, soaked in syrup or pickled in vinegar (with sugar, chili and garlic). Lotus rhizomes have a crunchy texture with sweet-tangy flavours and are a classic dish at many banquets, where they are deep-fried, stir-fried, or stuffed with meats or preserved fruits. Salads with prawns, sesame oil or coriander leaves are also popular. Unfortunately, fresh lotus root slices are limited by a fast browning rate. Lotus root tea is consumed in Korea.

Lotus root is a popular vegetable in Sri Lanka, where it is often cooked in coconut milk gravy. In India, lotus root (also known as kamal kakdi) is cooked as a dry curry or sabzi.

Japan is one of the primary users of the rhizomes, representing about 1% of all vegetables consumed. Japan grows its own lotus but still must import 18,000 tons of lotus rhizome each year, of which China provides 15,000 tons yearly.

Rhizomes contain high amounts of starch (31.2%) without characteristic taste or odor. The texture is comparable to a raw potato. The binding and disintegration properties of isolated Nelumbo starch have been compared with maize and potato starch; Nelumbo starch is shown to be superior as an adjuvant in the preparation of tablets. When dried, N. nucifera is also made into flour, another popular use of this vegetable.