Anacharis, American Frog's Bit, Brazilian Elodea, Waterweed, Planchon

Egeria densa

Family: Hydrocharitaceae
Genus: Egeria (ee-JEE-ree-uh) (Info)
Species: densa (DEN-suh) (Info)
Synonym:Elodea densa
Synonym:Anacharis densa


Ponds and Aquatics

Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Very high moisture needs; suitable for bogs and water gardens

Where to Grow:

Unknown - Tell us


12-18 in. (30-45 cm)


Unknown - Tell us


USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Sun Exposure:

Sun to Partial Shade


Unknown - Tell us

Bloom Color:

White/Near White

Bloom Time:

Late Summer/Early Fall


Unknown - Tell us

Other details:

May be a noxious weed or invasive

Soil pH requirements:

5.6 to 6.0 (acidic)

Patent Information:

Unknown - Tell us

Propagation Methods:

Unknown - Tell us

Seed Collecting:

Unknown - Tell us


This plant has been said to grow in the following regions:

Tuscaloosa, Alabama

Menlo Park, California

Orlando, Florida

Atlanta, Georgia

Cherry Valley, Illinois

Great Bend, Kansas

Holly Springs, Mississippi

Cleveland, Ohio

Lehigh Valley, Pennsylvania

show all

Gardeners' Notes:


On Apr 30, 2009, holeth from Corpus Christi, TX (Zone 9a) wrote:

This plant has escaped into many nearby streams, canals, etc. It forms densely vegetated areas in streams that previously had rocky bottoms. It is a problem.

Then again, land use changes gave it a better chance to invade:
> The trees/canopy were cleared along the banks of all of these habitats, letting in light.
> Nutrient sources abound. Non-point sources such as lawn fertilizers, and crop and pasture runoff are still problematic, despite major improvements. Trace nutrients need to meet trace levels.
> Land development re-routes runoff away from primary sources into storm sewers, which usually empty into larger rivers, often the one the streams meet...eventually. Diverting runoff slows the stream flow and reducing the total volume, making stream... read more


On Aug 26, 2004, jdurha from North Clarendon, VT wrote:

FYI: Egeria densa/ Brazilian Elodea is a Class A Noxious weed in Vermont. The importation, movement, sale, possession, cultivation and/or distributions is prohibited with fines upto $1000.00 possible


On Sep 9, 2003, pegkay53 from Great Bend, KS wrote:

I have grown anacharis for about 35 years. I have grown it in aquariums and outside ponds. It does best outside in full sun. Mine has winter over in zone 5 with little or no damage, as long as the pond does not freeze to the bottom. Some is left floating on the top of the water, other I have planted into 5 gallon bucket. I use peat moss on the bottom 1/4 of the bucket, follow by a good potting soil to within about 4" of the top. You must put at least 3-4" of sand on top to prevent the peat and potting soil from floating. Break off 8" or longer stem, make a hole with finger or stick 3-4" deep and place the broked end in the hole and gently press the dirt around the stem. You can also just let it float on top of the water.


On Aug 30, 2001, smiln32 from Oklahoma City, OK (Zone 7a) wrote:

Egeria densa is a good plant for beginners, and its rapid growth helps create a balance in the aquarium from the start. It can also help prevent algae because it absorbs a great number of nutrients from the water. The plant secretes antibiotic substances which can help prevent blue-green algae (a type of bacteria). The growth rate depends largely on the amount of light and nutrition available. Growth does not stop in unfavourable conditions, but the plant turns light in colour and the tendrils grow thin.