Which words or phrases tells us that the plants are overgrown in "The Listeners"?

In the mysterious and enigmatic poem "The Listeners" by Walter de la Mare, a traveler arrives at a house in the midst of a forest and knocks on the door multiple times. He receives no answer, but the poet says that "a host of phantom listeners" dwells in the house—they hear him but remain silent. Eventually the traveler gives up and rides away.
The atmosphere of the remote location contributes to the eerie quality of the poem. Several words and phrases indicate to the reader that the plants all around the house are overgrown. First of all, the house is not in a town but out in the forest, which suggests an area surrounded by overgrown plants. The poet mentions the "forest's ferny floor." Ferns are wild plants that grow throughout a forest.
The poem also refers to "the leaf-fringed sill," suggesting that the exterior of the house has not been kept up and that plants are growing up around the windows. Finally, the traveler's horse "champed the grasses" and "moved, cropping the dark turf," suggesting that the grass around the house is overgrown to the point that the horse can easily feed on it.