Thermopsis montana
false lupin
A suckering herbaceous perennial, up to 90cm high, with silky, silvery blue-green leaves with three oval leaflets, and spikes of yellow broom-like flowers in early summer and sometimes again in early autumn
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Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Blue | |||
|---|---|---|---|---|
| Summer | Yellow | Green Blue | ||
| Autumn | Green Blue | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing or East–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Fabaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Suckering
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling Pets (dogs): Harmful if eaten - for further information and contact numbers regarding pets, see the HTA guide to potentially harmful plants
- Genus
Thermopsis are lupin-like rhizomatous herbaceous perennials with erect stems, leaves with three leaflets, and yellow or purple flowers
- Name status
Correct
- Plant range
- NW USA
How to grow
Cultivation
Grow in well-drained soil in sun or partial shade; cut down faded flower spikes to just above ground level; dig out roots if the plant spreads into unwanted areas
Propagation
Propagate by seed or division in spring
Suggested planting locations and garden types
- Cottage and informal garden
- Prairie planting
- Banks and slopes
Pruning
No pruning required, but if the faded flower spikes are cut down to just above ground level there may be a second flush of flowering in early autumn
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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