Silphium laciniatum
compass plant
A large upright perennial, to 3m tall, with hairy, aromatic, fern-like leaves, to 50cm long, becoming smaller up the stems. In late summer and early autumn it bears narrow sprays of bright yellow daisies, each up to 12cm across
Size
Ultimate height
2.5–4 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Yellow | Green | ||
| Autumn | Yellow | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical details
- Family
- Asteraceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Silphium are robust herbaceous perennials with tall stems bearing simple leaves, aromatic when bruised, and loose clusters of yellow, daisy-like flowers in summer and early autumn
- Name status
Unresolved
- Plant range
- N America
How to grow
Cultivation
Grow in moderately fertile, moist, deep, neutral to slightly alkaline, heavy soil in full sun or partial shade
Propagation
Propagate by seed or division
Suggested planting locations and garden types
- Wildlife gardens
- Architectural
- Cottage and informal garden
- Flower borders and beds
Pruning
Cut back after flowering; stems may optionally be left until shortly before new growth begins the following season
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.