Dalea

Dalea

Dalea bicolor ( Silver Dalea )
A fast growing, rounded, medium-sized, deciduous shrub reaching a maximum size of 8 x 8 feet, that is native to western Texas.
The fine-textured foliage is silvery.
The deep bluish-purple flowers are borne during late summer into autumn.
It is hardy to 10 F but will also survive in zone 7 as a perennial ( regrowth is rapid from hard winter pruning or freeze-back ). It is extremely tolerant of heat and drought.

Dalea candida ( White Prairie Clover )
Also called Petalostemon candidus. A moderate growing, perennial, reaching a maximum size of 4 x 2 feet, that is native to dry prairies in central North America ( from Red Deer, Alberta to Kenora, Ontario to Indiana; south to Arizona to Alabama ). It is extinct in the wild in Ontario. It is a host plant for Dogface Butterfly.
The leaves are composed of 7 to 9 lance-shaped leaflets. The mid-green foliage turns to yellow during autumn.
The fragrant white flowers appear during mid-summer.
Hardy zones 3 to 8 in full sun on very well drained soil. It is very drought tolerant.

Dalea capitata ( Lemon Dalea )
A fast growing groundcover shrub reaching up to 2 x 6 feet, It is evergreen in mild climates, a perennial where freezes occur. It is native to Coahuilla state in Mexico. It makes an attractive groundcover.
The foliage is bright green.
The yellow flowers borne on dense spikes, up to 1 inch long, during spring and fall.
Hardy zones 7 to 10 ( tolerating 0 F ) in full sun on well drained soil. It requires full sun on well drained soil and is extremely heat tolerant. Cut back hard during early spring for denser more vigorous habit.

Dalea frutescens ( Black Dalea )
A fast growing, mounding, small evergreen ( deciduous in cooler climates ) shrub reaching up to 4 x 6 feet. It is native from southern New Mexico to western Texas; south into northern Mexico. Some records include: 2 years - 3 x 4 feet.
The foliage is lacy and silvery. The pinnate leaves can have up to 20 tiny leaflets ( each up to 0.2 inches long ).
The intense purple flowers are borne spring until fall ( mostly late summer into fall in cooler climates ).
Hardy zones 8 to 9 ( tolerating as low as 0 F...many clones barely hardier than 15 F ) and may even grow as a perennial north into zone 5. It requires full sun on well drained soil and is very drought tolerant. Fertilizer is not recommended. Older overgrown plants can be cut back hard during early spring to rejuvenate.

Dalea greggii ( Trailing Indigo Bush )
A fast growing, low, spreading, groundcover shrub, reaching up to 3 x 15 ( rarely over 1 x 7 ) feet. The stems root anywhere they touch the ground making this a great plant for erosion control and stabilizing banks. It is native to the Chihuahuan Desert from southern Arizona to central Mexico.
The pinnate-compound leaves are composed of 5 to 11 tiny, silvery leaflets, up to 0.2 inches long.
The rosy-purple flowers are borne late spring into summer, though often repeating sporadically after.
Hardy zones 7 to 10 on just about any very well drained soil, it prefers full sun but will tolerate partial shade. It is tolerant of extreme heat including reflected heat of parking lot islands. It is often slow to establish at first.

Dalea lutea ( Yellow Dalea )
A semi-evergreen to evergreen shrub reaching a maximum size of 6 x 6 feet, that is native to Mexico and Guatemala.
The foliage is silvery to deep green.
The yellow flowers are borne in clusters during late autumn.
Hardy zones 9 to 10 in full sun on well drained soil. It is very drought tolerant and also tolerant of extreme heat. Cut back by 2/3 in March.

Dalea pulchra ( Bush Dalea )
A fast growing, open, rounded, evergreen shrub, reaching up to 8 x 5 ( rarely over 5 ) feet, that is native to southern Arizona and southwest New Mexico. Some records include: 3 years - 5 feet.
The attractive foliage is silvery-gray. The pinnate leaves are composed of 2 to 4 oval leaflets, up to 0.5 inches long.
The abundant violet flowers are borne on terminal heads during early spring.
Hardy zones 9 to 10 ( tolerating 15 F ) in full sun on very well drained soil. It is very drought and extremely heat tolerant and overwatering can shorten its life expectancy. Rabbit browsing may damage young plants.

Dalea purpurea ( Purple Prairie Clover )
Also called Petalostemon purpureum. A slow growing, clumping perennial, reaching a maximum size of 3 x 2 feet, that is native to prairies and open woods in central North America ( from Athabasca, Alberta to Kenora, Ontario to Port Huron, Michigan; south to New Mexico to Texas to central Alabama ). It is endangered in Kentucky and Tennessee; extinct in the wild in Michigan.
The fine textured foliage is rich mid-green, turning to yellow during autumn. The trifoliate leaves are composed of 3 linear leaflets up to 0.8 inches long. The leaves are borne from deep red stems.
The abundant, rose-purple flowers are borne over a long period during early to mid summer. The flower heads are up to 2.5 inches in length. The flowers attract butterflies.
Hardy zones 3 to 8 in full sun on moist, fertile, well drained soil. Very drought tolerant and deep rooted ( up to 16 feet deep! ). The roots fix nitrogen as Trifolium ( true Clovers ) do. Resistant to rabbits but not deer.

* photo taken on Aug 25 2014 @ U.S. Botanical Gardens, Washington, DC

Dalea spinosus ( Desert Smoketree )
Also called Psorothamnus spinosus. It is a small deciduous tree reaching up to 25 feet, that is native to river valleys in southern California, southern Nevada, western and southern Arizona. Some records include: 2 years - 10 feet; 3 years - 15 feet; 4 years - 17 feet; 7 years - 19 feet; 11 years - 20 feet; largest on record - trunk diameter of 20 inches.
Thrives in both Tucson & Yuma. No freeze damage at 15 F at Tucson.
The masses of gray, spiny stems sparsely bear simple leaves, up to an inch in length.
The deep violet-blue flowers, up to 0.25 inches long, are borne on loose clusters during late spring.
Hardy zones 9 to 11 in full sun on well drained soil. It is extremely tolerant of drought as well as extreme heat.

* historic archive photos

Dalea versicolor 'Mountain Delight' ( Weeping Dalea )
A fast growing, open, spreading, semi-evergreen to evergreen shrub, reaching up to 4 x 5 feet, that is native to southern Arizona, southwest New Mexico and neighboring northern Mexico.
The fine-textured foliage is deep gray-green. The pinnate leaves are composed of 11 to 23 leaflets, up to 0.7 x 0.4 inches in size.
The violet-purple flowers appear in dense clusters, up to 1 inch long, during autumn into early spring.
Hardy zones 8a to 10, tolerates as high as 110 F. It requires full sun to partial shade on well drained soil. and is very drought tolerant. Cut back hard during mid-spring for a denser, more vigorous habit.

Dalea villosa ( Silky Prairie Clover )
Also called Petalostemon villosum. A perennial, reaching up to 2 feet, that is native to Montana, southwest Saskatchewan, much of North Dakota, central Minnesota, western South Dakota and central Iowa. It is critically endangered in Saskatchewan, Iowa and Wisconsin. It is found on prairie sandhills in the wild. The taproot may reach up to 5 feet deep.
The pinnate leaves, up to 1.5 inches long, are composed of 9 to 17 narrowly-elliptical leaflets up to 0.5 inches long. The soft densely-hairy foliage is gray-green.
The purplish-pink flowers are borne on dense bottlebrush spikes up to 4.8 inches long, during mid to late summer.
Hardy zones 3 to 6 in full sun on sandy, very well drained soil. Very drought tolerant, requiring just 12 inchs of average yearly precip.