textAdminOnlyNameForClipboard
Cape Rattle-pod
Crotalaria capensis
SA tree no: 225.12
English: Cape Rattle-pod, Cape laburnum, Eared Rattle-pod, Yellow Pea, Wild Pea
Afrikaans: Kaapse Klapperpeul, Geelkeurtjie, Wilde-ertjie
Xhosa: iHlolo Getyane
Zulu: uBukheshezane
Venda: Musumbudza-nduhu
Historical scientific names: Crotalaria capensis var. obscura, Crotalaria cecilaea
Crotalaria capensis, often called Cape Rattle-pod or Kaapse Klapperpeul, is a fast-growing, indigenous evergreen shrub or small tree. It is highly valued for its attractive bright yellow, pea-shaped flowers borne in showy sprays, and its distinctive inflated seed pods that rattle when dry, giving it its common name. This versatile plant adds vibrant colour and unique auditory interest to gardens.
Have you got a better picture?
If you don't mind us using it, please upload it by clicking the Upload button below (you must be logged in to do this)
Distinguishing features:
Bright yellow, pea-shaped flowers borne in long, pendulous sprays.
Trifoliate leaves (composed of three leaflets).
Inflated, hollow seed pods that produce a rattling sound when dry.
Young stems and new growth often have a velvety texture and a silvery-blue tinge.
Fast-growing shrub or small tree.
Overall appearance:
The Cape Rattle-pod (Crotalaria capensis) is a lovely and lively plant that stands out with its cheerful, bright yellow flowers and fascinating seed pods. It typically grows as a multi-stemmed shrub or a slender small tree, adorned with fresh green, trifoliate leaves, which can have a charming silvery-blue look when they are young. The most exciting part is its inflated, papery pods that create a delightful rattling sound in the breeze, hence its catchy common name.
Height:
Typically grows 2 to 5 metres tall, though it can reach up to 6 metres in optimal conditions.
Width:
Forms a multi-branched shrub 1.5 to 3 metres wide, or a slender tree form with a spread of 1-2 metres.
Leaves:
The leaves are alternate and trifoliate, meaning each leaf is composed of three leaflets. The leaflets are typically elliptic to obovate (egg-shaped with the broader end at the tip), measuring 2.5-7 cm long and 1.5-3 cm wide. They are bright green, often with a silvery-blue tint when young, and the undersides can retain a blue-green hue. The surface can be glabrous (smooth) to thinly pubescent (slightly hairy). The petioles (leaf stalks) are shorter than the leaflets.
Flowers:
The flowers are typical "pea" flowers, with a distinctive structure including a large upper petal (standard), two side petals (wings), and two lower petals fused to form a keel. They are bright yellow, often with reddish markings or edges, and are sweetly scented. The flowers are relatively large, typically 1.5-2.5 cm long. They are borne in showy, erect to pendulous racemes (elongated clusters) at the ends of branches, with each cluster containing many flowers. Crotalaria capensis flowers are hermaphroditic, containing both male and female reproductive parts.
Flowering season:
Flowers mainly from spring to autumn (October to April), with a peak in mid to late summer. It can often have sporadic blooms throughout the year in mild climates.
Fruits:
The fruit is a distinctive, inflated, oblong-clavate (club-shaped), hollow pod, typically 4.5-6.8 cm long. It is light green when young, ripening to a light brown or straw colour. The pods are indehiscent (do not split open when mature) and when dry, the loose seeds inside rattle when shaken or moved by the wind, giving the plant its common name.
Seeds:
The seeds are small (4-4.5 mm long), oblique-cordiform (heart-shaped at an angle), smooth, and brown. They are loose within the dry, inflated pods, which aids in their dispersal.
Bark/Stems:
The stems are slender and green when young, becoming more woody and brownish with age. New stems are often velvety to the touch. The bark on older stems is light-coloured. The plant tends to be multi-stemmed from the base but can be trained into a single-stemmed small tree.
Thorns:
None.
Wood:
The wood is yellowish with a darker brown heartwood. It is heavy and hard but not extensively used for timber due to the plant's size.
Roots:
As a member of the legume family (Fabaceae), Crotalaria capensis has a symbiotic relationship with nitrogen-fixing bacteria in its root nodules. These bacteria convert atmospheric nitrogen into a form usable by the plant, enriching the soil. It has a relatively well-developed root system that helps with stability.
Soil type:
Tolerant of a wide range of well-drained garden soils, including sandy, loamy, and clay soils. It prefers soils enriched with compost and benefits from high fertility. It can adapt to soils ranging from acidic to slightly alkaline. Good drainage is essential.
Aspect:
Thrives in full sun, though it can tolerate some afternoon shade. It prefers moderate to good rainfall and is not very drought-hardy, so it will need regular watering during dry periods, especially in summer-rainfall regions. It is very wind-tolerant and hardy to moderate frost, tolerating temperatures below 0°C once established, but young plants should be protected from severe frost.
Ediblity:
Not typically considered edible for humans. While some Crotalaria species have edible parts in other regions, C. capensis is not known for human consumption.
Toxicity:
Like many species within the genus Crotalaria, Crotalaria capensis is known to contain pyrrolizidine alkaloids, which can be toxic if ingested. These alkaloids can cause liver damage in animals, particularly livestock, though not all Crotalaria species are equally toxic. While specific documented cases for human poisoning from C. capensis fruit or foliage are less common, it is prudent to consider all parts of the plant as potentially toxic and advise against ingestion. Keep away from curious children and pets.
Uses:
Highly valued as an ornamental plant in gardens for its showy yellow flowers and attractive foliage.
Excellent as a decorative hedge, informal shrub border, or screen due to its fast growth and multi-stemmed habit.
Can be pruned and trained into an attractive small specimen tree for smaller gardens.
Used in informal beds to add colour and structure.
Beneficial for soil improvement due to its nitrogen-fixing capabilities.
The dry pods with rattling seeds can be an interesting auditory element in the garden.
Ecology:
The bright yellow, scented flowers are mainly pollinated by carpenter bees, which are attracted to the nectar and pollen. Sunbirds and butterflies may also visit the flowers. The larvae of certain blue butterflies (family Lycaenidae) are known to parasitise the seed pods. Chameleons are often found hiding among the leaves, waiting to prey on adult butterflies and other insects. As a legume, it forms a symbiotic relationship with nitrogen-fixing bacteria in its roots, which enriches the soil, making it a valuable pioneer plant in disturbed areas, helping to make the soil more habitable for other plants. It is browsed by buck and livestock in natural habitats.
Distribution and habitat:
Crotalaria capensis is indigenous and widespread along the eastern Escarpment of South Africa, found in the Western Cape, Eastern Cape, KwaZulu-Natal, Free State, Mpumalanga, and Limpopo provinces. Its natural range extends northwards into Eswatini (Swaziland), Mozambique, eastern Zimbabwe, and southern Malawi. It grows in a variety of habitats, including fynbos, thicket, grassland, forest margins, along rivers and streams, and in coastal bush. It can also persist in disturbed places.
Derivation of name:
The genus name Crotalaria comes from the Ancient Greek word 'krotalon', meaning 'castanet' or 'rattle', referring to the rattling sound the mature seeds make inside the dry, inflated pods. This is the same root word as for "rattlesnakes" (Crotalus).
The species epithet capensis is Latin for 'of the Cape', indicating its prevalence in the Cape region of South Africa.
The common name "Cape Rattle-pod" directly refers to its origin and the sound of its seed pods.
"Cape Laburnum" is also used due to the resemblance of its flowers to the European Laburnum, but this can be misleading as they are not closely related.
Historical aspects:
Crotalaria capensis has been cultivated in Europe for over 200 years, indicating its early recognition as an ornamental plant. Its fast growth and attractive flowers made it a desirable species for gardens. Within its native range, its ecological role as a nitrogen-fixer and a pioneer plant has always been important. The traditional use of some Crotalaria species for various purposes (though C. capensis is not widely documented for human use) highlights the long-standing interaction between these plants and local communities.
Interesting facts:
This plant is named "Rattle-pod" because when its seed pods dry out, the seeds inside shake and make a fun rattling sound, just like a musical instrument!
Even though it's called "Cape Laburnum" sometimes, it's not actually related to the European Laburnum – it just has similar sunny yellow flowers!
As a member of the pea and bean family, it's a soil superhero! It has special bacteria in its roots that pull nitrogen from the air and put it into the soil, making the ground more fertile for other plants.
Chameleons love to hang out on this bush, using its leaves as a perfect hiding spot while they wait to catch their next meal – usually a butterfly!
Growing tips:
Propagation: Easily grown from seed. Soak seeds in hand-hot water overnight before sowing to improve germination. They typically germinate in about two weeks. Can also be propagated from cuttings.
Light: Prefers full sun for best flowering, but tolerates some afternoon shade.
Watering: Requires moderate to good rainfall. Water regularly, especially during dry spells, as it has poor drought tolerance for a South African indigenous plant.
Soil: Adaptable to most well-drained garden soils. Enhance with compost for optimum growth.
Container: Can be grown in large containers when young, but its size will eventually require planting in the ground.
Maintenance: Fast-growing; prune lightly after flowering to maintain shape and encourage bushier growth. Protect young plants from severe frost.
This plant is a fantastic alternative for:
Common name
Scientific Name
Plant type:
Plant type
Plant family:
Plant family (derivation)