Flowering Rush

Butomus umbellatus

Family: Butomaceae
Genus: Butomus (BEW-toh mus) (Info)
Species: umbellatus (um-bell-AY-tus) (Info)
Synonym:Butomus caesalpini
Synonym:Butomus floridus
Synonym:Butomus floridus


Ponds and Aquatics

Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Very high moisture needs; suitable for bogs and water gardens

Where to Grow:

Unknown - Tell us


4-6 ft. (1.2-1.8 m)


18-24 in. (45-60 cm)


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:

Full Sun


Unknown - Tell us

Bloom Color:


Bloom Time:

Late Summer/Early Fall



Other details:

May be a noxious weed or invasive

Soil pH requirements:

Unknown - Tell us

Patent Information:


Propagation Methods:

Unknown - Tell us

Seed Collecting:

Unknown - Tell us


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

Merced, California

Erie, Michigan

Saint Cloud, Minnesota

Gardeners' Notes:


On Feb 23, 2014, coriaceous from ROSLINDALE, MA wrote:

Trade, sale, purchase, transportation, and planting of this species is illegal in 3 states. It invades and destroys natural wetland habitat. It's a problem in 16 states and 8 provinces.


On Mar 15, 2008, distantkin from Saint Cloud, MN (Zone 4b) wrote:

Flowering rush (Butomus umbellatus) is on the Minnesota DNR invasive list
"Ecological Threat:

* Flowering rush is actively expanding. It has spread from a limited area around the Great Lakes and the St. Lawrence river to sporadically appear in the northern U.S. and southern Canada.
* It competes with native shoreland vegetation.
* It is a Eurasian plant that is sold commercially for use in garden pools. It is now illegal to buy, sell or possess the plant.
* There is documentation from a site in Idaho, between 1956 and 1973, where flowering rush appeared to be out-competing willows and cattails.
* Flowering rush is on the DNR Prohibited exotic species list in Minnesota."