Amorpha fruticosa
bastard indigo
A vigorous deciduous shrub of spreading habit, with leaves composed of up to 30 oval leaflets, and slender racemes to 15cm in length, of deep purple flowers with orange anthers
Size
Ultimate height
2.5–4 metresTime to ultimate height
10–20 yearsUltimate spread
2.5–4 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
West–facing or East–facing or South–facing or North–facing
Exposure
Exposed or ShelteredDrought resistance
Yes Hardiness
H6Botanical details
- Family
- Fabaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Genus
Amorpha are deciduous shrubs with pinnate leaves and racemes of tiny, single-petalled, deep purple or blue flowers in summer
- Name status
Correct
- Plant range
- S USA
How to grow
Cultivation
Grows well in light sandy soil and can survive in very poor soils. Tolerant of extreme cold
Propagation
Propagate by seed in autumn. Seed must be scarified as they have hard seed coats. Use sandpaper or a file to scarify (abrade) the seed coat. Chit the seed either by using a knife to nick the seed coat or by soaking the seed in warm water for 24 hours. Care should be taken when soaking seed, as too much can cause rotting. Sow at any time of year 2mm deep in moist, free-draining, quality seed compost. Propagate at 10-15C in a greenhouse, on a windowsill or in a coldframe outdoors in spring. Germination should take place in 30-120 days
Suggested planting locations and garden types
- Low Maintenance
- Flower borders and beds
Pruning
Pests
Generally pest-free
Diseases
A rust may occur (N. America only)
Get involved
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