Family: Pontederiaceae
Common name: Water hyacinth, Common water hyacinth, Lilac devil, African payal
Water hyacinth is a very common aquatic plant seen in ponds, rivers, lakes, and other freshwater bodies. They are native to South America, but are now widely distributed across all tropical and sub-tropical countries, where they are infamous for their invasive tendencies.
Plant Characteristics
The roots and stems of the Water hyacinth are designed help them float on the surface of the water. Roots are long and feathery, growing up to a meter long, keeping the plant afloat and also absorbing nutrients from the water for the plant to grow rapidly.
Stems of Water hyacinth are soft, spongy and airy with bulbous structures at the base to hold more air. The bulbous structures can pop with a loud noise when stamped on, making it really fun for the kids to pull out water hyacinths and step on them. When placed on the ground, the plants dry up very quickly.
Water hyacinths grow very quickly, one of the reasons they are highly invasive. The mats or clumps of plants can double in size in a few days, each plant producing multiple smaller plants through interconnected root stolons, and seeds.
The plant grows to a height of 30-60 cm with glossy, green leaves that are 15-25 cm long. They are arranged in rosettes at the base of the plant with long stalks that keep that floating on the surface. The leaves are spoon-shaped, allowing the water falling on it to slide down immediately without staying on the surface of the leaf.
Flowers are one of the most attractive features of this plant, beautiful purple flowers held above the surface of the leaves on tall stalks. They are 3-4 cm in diameter with 6 distinct petals each having a darker purple base.
One of the petals has a yellow spot, adding to the overall beauty of the flower. When in full bloom, the Water hyacinths can look like a large green meadow filled with purple flowers.
Water hyacinths bloom during warmer months like spring and autumn, each flower living only for a day, but the profusion of flowers ensure that the plant is always covered with beautiful purple flowers that attract insects, bees, and other pollinators.
Though these plants do not produce any fruits, the flowers can produce seeds after pollination. These seeds are small, hard and designed to be dispersed by water. They can sink to the bottom or stay afloat, viable for germination even after a couple of decades.
Gardening Tips
When grown in controlled environments like small ponds or water gardens, the number of Water hyacinth plants can be kept in check. So they are good aquatic plants that are easy to grow and propagate.
Just get a small piece of water hyacinth from a river or lake and place it in the water body at home. They will grow rapidly producing new plants in a matter of days.
They need good sunlight and nutrient-rich, slow-moving water.
Make sure you remove excess plants from the water since they can deplete the water of oxygen, preventing the growth of fishes.
They do not grow well in colder climates, and would need to be grown in glass houses. Water hyacinths are not indoor plants, and cannot be grown in aquariums.
Uses of Water hyacinths
Though these plants are considered as invasive weeds, these plants can be used to remove pollutants and heavy metals from water bodies. They can be used to produce compost because of the enormous quantities of biomass they produce in a short period of time.
Water hyacinths are eaten by cows and pigs. The plants can be used in mulching helping keep the soil moist for a longer period. They can be used for making biofuel, and also in paper making.
The small ecosystem produced by the roots of Water hyacinths provide a safe space for small fishes and other animals to stay protected from predators and from natural elements.
In spite of these benefits, Water hyacinths are notorious for invading and filling water bodies, affecting fishes and other aquatic animals. Every year, governments and local bodies spend a lot of money to remove excess water hyacinths from rivers and lakes, only to have them come back again very very quickly.
Propagation
Propagation is through seeds and stolons.
Vegetative propagation through stolons is very quick and efficient, each parent plant capable of producing hundreds of smaller plants in a short period of time. Seeds collected from parents plants can be sowed directly in water to germinate and produced new plants.
Photographed at: Koonammavu, Kerala
