Silphium laeve
Family: Asteraceae or Compositae
What it is like
Silphium laeve is a PERENNIAL. See above for USDA hardiness. It is hardy to UK zone 4. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Height (m): 0
Where it is found
Not known
N. America.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 1
Root. No more details are given in the reports.
Root: includes bulbs, corms, tubers, rhizomes etc.
Medicine
Rating: 0
Other
Rating:
How it is grown
We have very little information on this species and do not know if it will be hardy in Britain. The following notes are based on the general needs of the genus. Succeeds in any ordinary garden soil. Prefers a deep moisture retentive moderately fertile soil that is not too nitrogen rich, in sun or dappled shade. Plants have a deep and extensive root system which makes transplanting difficult.
Propagating it: Seed - best sown as soon as it is ripe in a greenhouse. Prick out the seedlings into individual pots as soon as they are large enough to handle and plant them out in the summer. Division in spring. This is very difficult due to the deep and extensive root system.
Best place to grow: Cultivated Beds;
Habit: Perennial
Hardiness: 4-8
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Moist