About
Silphium perfoliatum (Dixter Form) is an erect herbaceous perennial in the Asteraceae, notable for its yellow, daisy-like composite flower heads. Flowering runs from July to September. Leaves are triangular and toothed and the stems are stout and square‑angled. It is typically used where a tall, architectural summer presence is wanted.
About the genus
Silphium is an unidentified plant that was used in classical antiquity as a seasoning, perfume, aphrodisiac, and medicine.
Wikipedia contributors, "Silphium", CC BY-SA 4.0 — Silphium
In the garden
Silphium perfoliatum (Dixter Form) belongs to the genus Silphium in the family Asteraceae and carries the common name Cup Plant. It originates from North American landscapes where it occurs in wetter ground; its most visible feature in cultivation is the summer display of yellow composite flowers between July and September. Choose a position that does not dry out completely: the species is associated with floodplain and streamside habitats and performs best in reliably moist soil. It tolerates open situations and the edges of light woodland, so place it at the rear of a mixed border or alongside ponds and rain gardens where its upright stems can be accommodated. Stout, angled stems carry triangular toothed leaves and support the summer flower heads without excessive staking in most sites. Allow room for its height when planning the border and pair it with plants that tolerate damp soil and full sun to partial shade. The Dixter Form is valued for long‑season flowering and its structural presence; note that the leaf bases clasp the stem and can hold small amounts of water after rain, a distinctive feature to observe in summer.
