Whorled rosinweed
Silphium trifoliatum

Family: Compositae

What it is like

Silphium trifoliatum is a PERENNIAL growing to 1.8 m (6ft) by 1.8 m (6ft) at a medium rate. See above for USDA hardiness. It is hardy to UK zone 5. The flowers are pollinated by Bees, Insects. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers dry or moist soil.

Height (m): 1.8

Where it is found

Open, grassy areas such as prairies, river cobble bars, and roadsides.

Native to the eastern United States east of the Mississippi River.

Conservation Status: Not Listed.

Countries/locations it is found in

How it is used

Food

Rating: 0

Dave Jacke in his book Edible Forest Gardens has noted that this plant is edible although we have been unable to find any confirmation. Other Silphium species are edible for example Silphium integrifolium produces an protein-oil staple Crop and Silphium laciniatum resin is used as a chewing gum to sweeten the breath.

Medicine

Rating: 0

Other

Rating: 2

Invertebrates shelter: beneficial for insects and other arthropods. Nectary: provides nectar or pollen for beneficial insects. Garden Ornamental. More manageable than most perennial sunflowers as it spreads slowly, and it is not known to be allelopathic. Adapts well to prairies, wildflower/native plant gardens, naturalized areas, meadows or moist, open woodland areas. Attracts birds and butterflies

How it is grown

A tall perennial forb for full to partial shade. Leaves are attached to the stem in a 'whorled' formation. Sun Exposure: Full, Partial. Soil Moisture: Medium, Medium-Dry. Drought-tolerant; suitable for xeriscaping. Bloom Time: July to September. Bloom Color: Yellow. For polyculture design as well as the above-ground architecture (form - tree, shrub etc. and size shown above) information on the habit and root pattern is also useful and given here if available. The plant growth habit is a runner spreading indefinitely by rhizomes or stolons.

Propagating it: Seed. Plants may be slow to establish in the garden, particularly when grown from seed. Plants often self-seed in optimum growing conditions. Division.

Best place to grow:

Habit: Perennial

Hardiness: 4-6

Growth: Medium

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Dry, moist

Things to keep in mind

Its other names

Local names

Whorled Rosin Weed

Synonyms

No synonyms are recorded for this name.