Colutea arborescens (southern Europe)
Habit: Upright to domed normal shrub, 1-3 m tall and wide, slow-growing.
Flowers: Conspicuous, yellow butterfly flowers; luxurious first flowers in May, second blossoms from June to end of September.
Fruits: Balloon-like, decorative pods, reddish-green, translucent, from June with the flowers.
Leaves: Pinnate, fresh green, pale yellow from beginning of October.
Roots: Deep roots, collect nitrogen.
Demands: Only in full sun, in warm, dry areas, takes very well to heat, moderately frost hardy, wind resistant.
Soil: Very dry to fresh, on all well drained, chalky substrates, not too nutritious; tolerant of salt.
Hardiness: Zone 6a