butterbur, bog rhubarb
蕗 refers to a specific plant: butterbur or bog rhubarb. The meaning is narrow and botanical, without a broader abstract center.
蕗 combines the grass radical 艹 with 路, which likely contributes the sound. The character was created to name the butterbur plant.
The grass radical 艹 sits above 路, like a plant growing along a path. Picture butterbur leaves lining a roadside.
For ロ, imagine a row of butterbur plants growing low along the path: row -> ロ, and the low plants line the road.
giant butterbur (Petasites japonicus); Japanese sweet coltsfoot
stalks of butterbur boiled in soy sauce
wild giant butterbur
Parasenecio farfarifolius var. bulbifer (variety of Indian plantain)
leopard plant (Farfugium japonicum); Japanese silverleaf
Japanese butterbur (Petasites japonicus subsp. giganteus)
edible flower bud of a giant butterbur plant
liquorice; licorice
Saxifraga japonica (species of saxifrage)
Adenocaulon himalaicum (species of flowering plant)