Accepted Scientific Name: Dudleya pulverulenta (Nutt.) Britton & Rose
Bull. New York Bot. Gard. 3: 13 1903
Echeveria pulverulenta (Dudleya pulverulenta) Photo by: Diego Armentano
Origin and Habitat: Dudleya pulverulentaSN|32582]]SN|32582]] has the widest range of any dudleya, over 1000 kilometers, from Central Baja California (Mexico), to California (San Luis Obispo County, east in San Diego County to the western margin of the Colorado Desert, where apparently it intergrades with the subsp. arizonica) USA.
Altitude range: 0-1500 metres above sea level.
Habitat and ecology: Upper Sonoran Zone in Coastal Sage Scrub, Chaparral. Dudleya pulverulentaSN|32582]]SN|32582]] grows in arid coastal side of mountains on near-vertical rocky cliffs, canyons and embankments. In this area they grow in winter and spring. Summer is a resting period after the winter rains ), but the plants obtain additional water from condensation of coastal fog. Hummingbirds often visit Dudleya pulverulentaSN|32582]]SN|32582]], its open inflorescence, together with its pendent flowers on long, slender pedicels, long red corolla with long tube, and high nectar yield, seems especially adapted to them as pollinators, having, for example, about the longest corolla, with the longest tube, and the highest nectar output.
Synonyms:
See all synonyms of Dudleya pulverulenta
Common Names include:
ENGLISH: Chalk dudleya, Chalk liveforever, Chalk Lettuce, Chalky live-forever, Powdery liveforever
Description: Dudleya pulverulentaSN|32582]]SN|32582]], also known as the Chalk Dudleya, belongs to a large group of succulents in the stonecrop family (Crassulaceae). It is a perennial plant forming a rosette of succulent leaves from a thick caudex, it gets its silvery-white colour from a coating of fine white mealy powder. The dense, white, mealy powder or chalky wax also sepals, stems, leaves, and underside of flowers. Rosettes send up long, arching flower spikes in late spring. Dudleya pulverulentaSN|32582]]SN|32582]] is one of the largest and most distinctive species of the genus, easily recognized from a distance, even without flowers.
Rosettes: 25-60 cm in diameter, solitary, not in clumps, containing about 30-80 leaves. In summer, rosette dudleyas close up to protect their cores from sunburn and desiccation.
Stem (caudex): Mostly unbranched, becoming decumbent, 4-8.5(-10) cm thick, to 40(-50) cm long, densely covered with old dried leaves. Axillary branches absent.
Leaves: Thick, succulent, chalky-pulverulent, obovate-spatulate, oblong, widest at base or in distal 1/3,and coming to a point, 8-27(-30) cm long, 3-10(-13) cm. wide, 3-10 mm. thick, base 3-8 cm wide, base 3-8 cm wide. Floral-stem leaves smaller and clasping.
Inflorescences (cymes): Floral stems, erect, stout, 30-100(-150) cm tall, 5-15(-20) mm thick, with about 30-70 ovate to suborbicular, acuminate leaves becoming red, densely 2-5-branched, branches twisted at base (flowers on underside), simple or 1 times bifurcate. All parts of the flowering shoot often are farinose. Cincinni 3-6 or several, spreading or ascending, 10-40 cm long, with 10-30 flowers. Pedicels 1-3.5 cm long.
Flowers: Campanulate, red, mostly pendent in bud, declined or pendent at anthesis, becoming erect by a bending of pedicel near or above middle.Calyx 5-9 × 5-8 mm. Sepals triangular-ovate, acute, 4-8 mm long, 3-4 mm wide. Corolla red, 11-19 mm long, tube 6-10 mm. Long. Petals connate for 6 10 mm, oblong, red, acute to obtuse, free part 5-9 mm long, 2-4 mm wide, apex acute to obtuse, tips erect. Ovaries 6-12 mm long. Styles 1-2 mm long.
Blooming season: Early summer (May-Aug.)
Fruits:: Follicles more of less erect.
Deeds: Slender, brown.
Chromosome number: 2n = 34.
Subspecies, varieties, forms and cultivars of plants belonging to the Duddleya polverulenta group
Dudleya pulverulenta (Nutt.) Britton & Rose- Dudleya pulverulenta var. arizonica (Rose) S.L.Welsh: looking like a reduced desert form of D. pulverulenta, smaller in most parts, or sometimes like a seedling. Distribution: S. Nevada, W. Arizona (USA) and Baja California and Sonora (Mexico).
Bibliography: Major references and further lectures
1) Forrest Shreve, Ira Loren Wiggins “Vegetation and Flora of the Sonoran Desert”, Volume 1 Stanford University Press, 1964
2) Debra Lee Baldwin “Succulents Simplified: Growing, Designing, and Crafting with 100 Easy-Care Varieties” Timber Press, 21 May 2013
3) Marjorie G. Schmidt “Growing California Native Plants” University of California Press, 29 December 1980
4) Unknown,“Dudleya pulverulenta” in Flora of North America @ efloras.org <http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242412989> FNA Vol. 8 Page 172, 175, 178, 191 accessed on 27 February 2016
5) Laird Blackwell “Wildflowers of California: A Month-by-Month Guide” University of California Press, 08 May 2012
6) Paul Thompson “Dudleya and Hassenthaus Handbook”, 1993
7) Wikipedia contributors. "Dudleya pulverulenta." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 19 Sep. 2015. Web. 27 Feb. 2016.
8) Urs Eggli “Illustrated Handbook of Succulent Plants: Crassulaceae” Springer Science & Business Media, 01 January 2003
Cultivation and Propagation: This slow growing specie is often grown and makes an attractive plant. It is much admired but less easily grown than some others. Grow it as a house or conservatory plant in a porous mix, or as a garden perennial where winters are mild and summers dry. Dudleyas are hardy in USDA Zoned 9-12, the plant is highly heat and drought tolerant during the summer months and prefers moist cool winters. Powdery white leaves make these plants standouts, but avoid touching them as they are easily and permanently marked by finger marks. All of the plants in the Dudleya genus are known to live up to 100 years.
Soil: They do best in very well-drained, sandy or gravely soil. As an ornamental it is also grown in containers where it stays smaller than its outdoor brethren. In pots they need a very porous mix soil (e.g. 2 parts peat moss to 1 part loam to 1 part of pumice).
Exposure: It requires ample sun, but provide midday shade where summers are hot. The quality of light is much more important than the quantity, the plants contain farinose powder which makes them really effective for ultraviolet reflectivity. Low light situations might be stressful and create a susceptibility to mealy bug infestation.
Watering: Dudleyas are summer-dormant winter growers that require fresh air, exceptionally well- drained soil, and don't water them in summer even if they appear crisp and miserable; they're dormant and unused to summer rainfall. However, they do appreciate an occasional misting suggestive of coastal fog (provide water in spring and autumn). In the summer the roots are unable to absorb the water so any excess of water simply rots them because of their dormant state.
Maintenance: Remove spent flower stems for appearance. The older leaves of Dudleyas wither but remain attached to the stem. Whether or not they should be removed is disputed, but they provide a hiding place for pests and some growers preference to remove them.
Uses: This can become a beautiful pot plant with pretty inflorescences with the right care.
Propagation: Dudleyas has been found to be propagated through both seed and vegetative, although vegetative propagation by offsets in spring or early summer is not only more popular but it is much easier to do. Dudleya should be planted at an angle. This prevent s the buildup of water in the leaves, which may lead to the leaves rotting. The vegetative propagation process needs to be done with temperatures reaching 21 degrees C. Let dry the cutting for about five to ten days and put the the cutting into the rooting compost (2 parts perlite and 1 part cactus potting mix). After finishing this you then place the pot in a warm, sheltered, but very bright filtered light area with no direct sunlight, you do not want the leaves to dehydrate. During the rooting period make sore to limit water, the rooting will take around 2 weeks, after roots transplant into the growing container. One thing to remember when rooting cuttings, overhead watering is not good for it, apply only to the soil line. The seeds do not need to be covered but do need a moistened soil for germination. Placing them into a mist house at an optimal 20-21 degrees Celsius with sufficient lighting resulting in germination. Germination occurs in just two weeks.
