- Floating Water Hyacinth
- Common Water Hyacinth
General: Water Hyacinth is an aquatic herbaceous evergreen perennial in the Pontederiaceae family.
Flowers: Showy flower spikes are composed of 4- 15 individual flowers. Each flower has 6 purple to pink petals. The upper petal displays a darkened spot with a yellow center.
Stems: Are bulbous and spongy, growing up to 50 cm long.
Leaves: Kidney-shaped leaves with inflated bases (air bladders) form free-floating rosettes. They are thick, waxy and glossy. Leaves are 10 – 20 cm wide.
Seeds: Thin-walled, ribbed capsules contain as many as 450 egg-shaped seeds.
Roots: Long, dark purple to black roots dangle below the rosette. Roots are highly divided and appear feather-like. As much as 50% of Water Hyacinth’s biomass is found in the roots.
Pickerelweed (Pontederia cordata) is a non-native aquatic plant present in British Columbia. Relative to Water Hyacinth, it has smaller leaves, forming a long, slim spike. In addition, Pickerelweed leaves do not have air bladders and do not form dense mats.
Water Lettuce (Pistia stratiotes) is an invasive aquatic plant present in British Columbia. Water Lettuce can be distinguished by its lettuce head-shaped rosette and inconspicuous white flowers. Moreover, it lacks a bulbous stem.
Habitat and Origin
Water Hyacinth is native to South America and was introduced to the United States in the 1880s.
The aquatic plant favours nutrient-rich waters and warm climates. It frequently inhabits shallow ponds, wetlands and marshes or slow-flowing waterways, lakes and rivers. In the Pacific Northwest, it is often planted outdoors in pools and water features but is not considered winter hardy.
Propagation & Vectors of Spread
Water Hyacinth reproduces prolifically by vegetative means by forming daughter plants that sprout from stolons (underground stems). To a lesser degree, it reproduces by seed, though Water Hyacinth seeds may germinate after being dormant for up to 28 years. In ideal conditions, Water Hyacinth can double its population within 2 weeks.
Water Hyacinth disperses primarily through vegetative reproduction. However, seeds are also dispersed by wind, water and human activities. In addition, it is commonly sold at nurseries for its showy flowers.
Ecological, Economic, & Health Impacts
- Outcompetes and displaces native vegetation.
- Reduces biodiversity.
- Reduces oxygen levels in the water, altering the entire aquatic ecosystem.
- Decreases overall water quality by releasing heavy metals and other pollutants.
- Creates a favourable habitat for mosquitos.
- Forms dense floating mats that slow water flow and block irrigation canals, increasing maintenance costs.
- Dense mats also disrupt recreational activities.
What Can I Do?
Water Hyacinth is not currently found in the Sea to Sky, so PREVENTION is key:
Learn to identify Water Hyacinth: use the images presented on this profile page to learn how to identify Water Hyacinth.
What to do if you spot it: You can report any Water Hyacinth sighting by clicking here.
- Regularly monitor properties for invasive infestations.
- Clean, Drain, Dry all watercraft. Rinse all mud, debris and plant fragments from all equipment, wading gear, and boats.
- Ensure all plant parts are bagged or covered to prevent spread during transport to designated disposal sites.
- Store boats in infested areas; remove plant material from any equipment, boats or clothing used in such areas and wash equipment and boats at designated cleaning sites before leaving infested areas.
- Plant Water Hyacinth in an aquarium or water garden, no matter how well-contained its enclosure may seem.
- Compost any parts of the plant. Instead, dispose of Water Hyacinth in the general/household waste stream at the landfill as the seeds will be able to persist the composting process.
- Move soil or water that has been contaminated with Water Hyacinth.
- Very small infestations can be controlled by hand pulling, raking or seining from the surface of the water.
- Most mechanical control is labour intensive and costly.
- Herbicides cannot be applied in aquatic environments in Canada.
- Herbicide control is not recommended for this species.
- Many insect species have been investigated for use against Water Hyacinth, however, there are currently no biocontrol agents available in BC.
- Several weevil species are currently used in various parts of the United States.
- Aquatic Nuisance Species Task Force, Stop Aquatic Hitchhikers: Water Hyacinth, https://stopaquatichitchhikers.org/hitchhikers/plants-water-hyacinth/
- Fraser Valley Invasive Species Society, Water Hyacinth, https://fviss.ca/invasive-plant/water-hyacinth
- Invasive Species Council of Manitoba, Water Hyacinth, https://invasivespeciesmanitoba.com/site/index.php?page=water-hyacinth
- Invasive Species Council of Manitoba, Water Hyacinth Factsheet, http://invasivespeciesmanitoba.com/site/uploads/pdf/Other%20Information/fs_hyacinth.pdf
- King County, Water Hyacinth (Eichhornia crassipes), https://kingcounty.gov/services/environment/water-and-land/lakes/plants/weed-identification/water-hyacinth.aspx
- Tip of the Mitt Watershed Council, Water Hyacinth, https://www.watershedcouncil.org/water-hyacinth.html
- University of Florida, Eichhornia crassipes, https://plants.ifas.ufl.edu/plant-directory/eichhornia-crassipes/
- USDA National Invasive Species Information Center, Water Hyacinth, https://www.invasivespeciesinfo.gov/aquatic/plants/water-hyacinth