What Effects the Growth of Elodea in Water?
- Sprigs of elodea often don fish bowls and aquariums.Meiko Arquillos/Valueline/Getty Images
Native to much of North America's freshwater habitats, common elodea (Elodea canadensis) remains an easy-to-grow aquatic plant often used in aquariums. This species is regarded as a noxious weed in waterways across Europe, Asia and Australia today, where it escaped from cultivation in the past. To distinguish elodea from other plants that look like it, remember that common elodea's leaves occur in whorls of three leaves on the stems, according to an article in the "Journal of Aquatic Plant Management." - Authors of an article on Elodea canadensis management in the "Journal of Aquatic Plant Management" mention that soils affect the ability of the plant to colonize, or rapidly grow to fill a water body with stems and leaves. Elodea roots growing in silty soils yield faster shoot growth than less-nutritious sandy types.
- Soil or water rich in iron (Fe) molecules or ions increased growth of common elodea. When this aquatic plant invaded European waterways in the 1800s, scientists found that its weediness diminished where the water lacked iron nutrients. Moreover, a report from the California Department of Food and Agriculture notes that an environment with plentiful phosphorus and bicarbonates increases common elodea's growth rate.
- As a green plant, common elodea needs sunlight energy to make food for growth. Insufficient light levels slow growth since solar energy is lacking but the lack of warming infrared rays keeps water temperatures cooler, slowing growth rates. Full-sun exposures in open water allows leaves to produce food all day to support root, stem and flower production and the formation of seeds.
- The Journal of Aquatic Plant Management" notes that common elodea survives being suspended in ice over winter and continues to grow slowly in winter if in cold water under ice, too. Plant growth increases as water temperature increases. An ideal cultural range exists between 65 and 75 degrees Fahrenheit.
- Plants need carbon dioxide to metabolize the food made in their leaves. Water rich in aeration or expelled carbon dioxide from breathing fish and decaying vegetation helps increase stem and leaf growth. Competition for carbon dioxide gas in the water with other plants and algae slows growth or temporarily stops it.
