The species favours lowland areas that are seasonally wet but never inundated, such as the margins of swamps and marshes. For example, in the Yule Brook Botany Reserve, where parallel sand ridges cross a clay flat, "B. telmatiaea" occurs neither in the lowest parts of the flat, where seasonal inundation occurs; nor on the tops of the ridges, where the drainage is good; but it is one of the most abundant plants of intermediate habitats, on ridge slopes and in higher areas of the clay flat.