Crassula namaquensis Photo by: Giuseppe Distefano
Origin and Habitat: Southern Namibia southwards to the Namaqualand as the name strongly suggests, but also in the Richtersveld in South Africa.
Habitat and ecology: It grows among quartzite rocks.
Synonyms:
See all synonyms of Crassula namaquensis
Common Names include:
ENGLISH: Namaqua crassula
CHINESE (中文): 青锁龙属 玉杯
Description: Crassula namaquensisSN|32661]]SN|27547]] is a dwarf succulent shrub to 100 mm high having a stout base and clusters of spirally arranged leaves. These leaves are fuzzy, pale blue to blue-green due to the peculiar hairs which are thickly distributed over the surface. Flowers in a terminal head, white. It is related to Crassula tectaSN|27547]]SN|32661]].
Habit: Perennials with basal rosettes, with old leaves not deciduous.
Stems: Stout woody, more or less branched, with short stems trailing in the sand.
Leaves: Thickly succulent, oblong, elliptic to oblanceolate, erect, (4-)10-35 mm long (2-)3-10 mm broad, acute to obtuse, flat to somewhat convex above and usually very convex below to almost terete, velvety, densely covered with coarse recurved and adpressed hairs and without marginal cilia, grey- to bluish-green variably ridged in brown at the top, old leaves persistent.
Inflorescence: The inflorescence is a thyrse that usually produces one terminal spherical dichasium (occasionally up to 3 or more especially in cultivation). Peduncle 2-10 (14) cm long and covered with recurved adpressed hairs.
Flowers: Creamy white. Corolla lobes oblong-triangular, 2-3 mm long with rounded apices, with recurved hairs and marginal cilia, green to grey-green. Corolla tubular, fused basally for 0,6-1 mm, white, cream to yellow; lobes oblanceolate to almost panduriform, rarely narrowly elliptic, 3-8(-10) mm long, acute to acuminate and drawn into a beak-like apex without dorsal appendage. Stamens with black anthers. Squamae oblong-cuneate, 0,7-1,1 x 0,2-0,6 mm, entire or slightly emarginate, fleshy, yellow to orange.
Blooming season: Spring (in habitat between August and November).
Subspecies, varieties, forms and cultivars of plants belonging to the Crassula namaquensis group
- Crassula namaquensis Schönland & Baker f.: (subsp. namaquensis) has shorter leaves, stout woody stems and short, beaked white corolla lobes up to 10 mm long. Distribution: Kamiesberg, to south-eastern Namibia.
- Crassula namaquensis subs. comptonii (Hutch. & Pillans) Toelken: the leases are nearly terete, the corolla lobes are 2-3 mm long and yellow. Distribution: Nieuwoudtville area (Type: Cape, Van Rhyn's Pass)
- Crassula namaquensis subs. lutea (Schönland) Toelken: has conical acute leaves 15-30 mm long, corolla lobes very variable in length yellow 7-9 mm long. Distribution: Swart Ruggens Mountains and Cedarherg. (Type: Cape, Bokkeveld Karoo)
Bibliography: Major references and further lectures
1) Werner Rauh “The Wonderful World of Succulents: Cultivation and Description of Selected Succulent Plants Other Than Cacti” Smithsonian Institution Press, 1984
2) Doreen Court “Succulent Flora of Southern Africa” CRC Press, 01/giu/2000
3) Stuart Max Walters “The European Garden Flora: Dicotyledons” (Part I) Cambridge University Press, 1989
4) Gordon D. Rowley “The illustrated encyclopedia of succulents” Crown Publishers, 01/Aug/1978
5) Dr J.P. Roux “Flora of South Africa” 2003
6) Foden, W. & Potter, L. 2005. Crassula namaquensis Schönland & Baker f. subsp. namaquensis. "National Assessment: Red List of South African Plants" version 2013.1. Accessed on 2014/05/24
Cultivation and Propagation: Crassula namaquensisSN|27547]]SN|27547]] is not so difficult to cultivate if you remember not to over-water in the Summer when they're taking their rest. This is a small plant that is perfect for a window garden, dish garden that will take full sun, little water, the leaves are gray and look like upside down ice cream cones. It may be difficult to find but worth the bother. In cultivation it is a spring and autumn grower (summer dormant). When there is too much water available in combination with too less light, the leaves won't form the characteristic dense white hairs and you will see the green of leaves between the leaf hairs which will make the sight less pretty.
Soil: They are tolerant of a wide range of soils and habitats, but prefer a very porous potting mix to increase drainage. You can grow a plant in a 6-10 cm pot for years and have perfectly happy plants. For best results, use a shallow pot.
Watering: It is in theory a spring grower, but the area of origin is so dry that the plants are mostly oppportunistic and will grow when they are lucky enough to get water so provide some water all year around. So keep it on the drier side than other Crassulas. During the winter months, water only when the soil becomes completely dry. Wet soil quickly causes root and stem rot, especially during chilly winter months, but can re-root if taken care of. No water should ever be allowed to stand around the roots. Low ambient humidity is always needed. Roots will rot in ever damp soil.
Fertilization: The plants are fertilized only once during the growing season with a balanced fertilizer diluted to ½ the recommended strength.
Sun Exposure: A sunny position brings out the best colours, it should be protected from too much exposure in Summer. They do not do well in full shade as they tend to etiolate, and rot easily.
Pest & diseases: Crassulas are sensitive to mealybugs.
Rot: Rot is only a minor problem with Crassula if the plants are watered and “aired” correctly. If they are not, fungicides won't help all that much. Care must be given in watering, keeping them warm and wet while growing, and cooler and dry when dormant.
Hardiness: Although the plants will survive mild frost if kept dry (hardy as low as -5° C) they should be protected from frost to prevent scarring.
Use: It is an excellent potted plant great for windowsill culture as well as in rock gardens. Indoors only in brightest position.
Pruning: Remove dead flower spikes only.
Propagation: They are easily grown from seed. They can also be propagated by the removal of off shoots, remove a lateral shoot and insert the basal part buried in the soil. This shoot should root within a month.