Common Name: Purple Prairie Clover

General Information

Dalea purpurea is an erect, herbaceous perennial plant producing a cluster of stems 30 - 90cm tall from a woody rootstock that is usually black or brown, occasionally yellow[, ].
The plant is harvested from the wild for local use as a food, medicine and source of materials. It can be used in restoration projects for restoring native prairies.

Known Hazards

None known

Botanical References

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Range

N. America - Alberta to Ontario and New York, south to Arizona, Texas and Georgia.

Habitat

Dry desert and alluvial soils; at elevations up to 2,000 metres[]. Sandy prairies in Texas[]. Prairies, rocky open glades, along railroad tracks, and rocky or open woods[].

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	0.90 m
Pollinators	Bees, Butterflies
Cultivation Status	Wild

Cultivation Details

Dalea purpurea is a very cold-hardy plant, tolerating temperatures down to below -20°c. It grows best in regions with a mean annual rainfall in the range 400 - 500mm, but can tolerate 300mm[].
Requires a well-drained soil in full sun[]. A deep-rooted plant, it prefers a sandy loam with added leaf mould[]. It is found in the wild growing in soils ranging from clay loams to loamy sands, growing more vigorously on well drained sites and in moderately alkaline calcareous soils[]. This species is well-suited to informal and naturalistic plantings, especially as part of a collection of native species[]. Established plants are moderately drought tolerant[].
The stems, leaves and flowers are dotted with glands, making the plant look blistered[].
This species is closely related to Dalea compacta and sometimes hybridizes with it in the wild[].
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[].

Edible Uses

The root was used for chewing[]. A pleasant sweet flavour, it is sometimes chewed like a gum[].

Leaves - raw or cooked[]. Eaten fresh or boiled[].
The dried leaves are a tea substitute[, ].

Medicinal

A poultice of the steeped bruised leaves has been applied to fresh wounds[].

A decoction of the leaves and blossoms has been used in the treatment of heart problems, diarrhoea[].

An infusion of the roots has been used in the treatment of measles, where it is said to reduce the fever[, ].

Agroforestry Uses:

Purple prairie clover is used in seed mixtures for re-vegetation and prairie restoration. It is a potentially useful plant for roadside and rest area beautification, park plantings and recreational garden natural area plantings. This species is also used in soil stabilization mixtures on dam face structures and critical area plantings[, ].

Other Uses

The tough, elastic stems have been made into brooms[].

Propagation

Seed - sow in early spring in a greenhouse. The seed has a hard seedcoat and benefits from scarification before sowing in order to speed up and improve germination. This can usually be done by pouring a small amount of nearly boiling water on the seeds (being careful not to cook them!) and then soaking them for 12 - 24 hours in warm water. By this time they should have imbibed moisture and swollen - if they have not, then carefully make a nick in the seedcoat (being careful not to damage the embryo) and soak for a further 12 hours before sowing. When they are large enough to handle, prick the seedlings out into individual pots and plant them out into their permanent positions in the summer[].
Seed stored cool and dry still has a 77% germination rate after 26 years[].