In all respects except frost hardiness, these are tough plants.
 They tolerate extreme heat, very low humidity, and prolonged drought.
 Like virtually all Proteaceae plants, they grow best on a light gritty soil with good drainage.
 They propagate from seed or half-hardened late summer-autumn cuttings.
This is a list of flora of the Lower Colorado River Valley (LCRV).
 The Lower Colorado River Valley is a floristic subdivision of the Sonoran Desert geographic region of the Southwestern United States.
 It includes plants that grow in the LCRV in Arizona, California, Nevada and Utah.
 This area of the Sonoran Desert has unique plant communities because it is it is the most arid part of the desert and it has the highest temperatures, in excess of 120 °F during the summer.
 The low humidity means that most plants must have mechanisms that deal with severe water loss through evaporation.
 The soils tend to be typical desert soils, coarse and without well-developed organic horizons, and plants can only obtain soil water during and very soon after the infrequent rains.
Kalmia is a genus of about 8 species of evergreen shrubs from 0.2–5 m tall, in the family Ericaceae.
 They are native to North America (mainly in the eastern half of the continent) and Cuba.
 They grow in acidic soils, with different species in wet acid bog habitats ("K. angustifolia, K. polifolia") and dry, sandy soils ("K. ericoides, K. latifolia").
Rhododendron ferrugineum (sometimes called alpenrose, snow-rose, or rusty-leaved alpenrose) is an evergreen shrub that grows just above the tree line in the Alps, Pyrenees, Jura and northern Apennines, on acid soils.
 It is the type species for the "Rhododendron" genus.
 It may grow up to 1 m tall and produces clusters of pinkish-red, bell-shaped flowers throughout the summer.
 The undersides of the leaves are covered in rust-brown spots, which give the species its scientific name.
 This is in contrast to "Rhododendron hirsutum", which has no such brown colouring, has hairy edges to the leaves and grows over limestone.
 Where the two species co-occur (usually on soils of intermediate pH), the hybrid "Rhododendron × intermedium" may occur; as its name suggests, it is intermediate in form between the two parental species.
San Benito Mountain is a mountain located in the Diablo Range of California.
 The highest point is at an elevation of 5267 ft .
 The rock is composed of asbestos (chrysotile), an ultramafic rock.
 It weathers to produce serpentine soils with characteristically low levels of nutrients like nitrogen, phosphorus, potassium, and calcium, and high levels of magnesium and heavy metals including nickel and chromium.
 This means little vegetation grows in the area though there are some plants that only grow on such soils like the local endemic San Benito evening primrose.
 Some of the highest peaks are clad in a unique pine and incense cedar forest.
Amelanchier interior is type of serviceberry shrub.
 It produces a sweet tasting edible fruit called a pome, which can be eaten raw or cooked.
 The fruit has a sweet flavor.
 This species is a deciduous tree.
 It grows on hillsides and banks of streams and reaches up to nine meters.
 The plant prefers light (sandy), medium (loamy) and heavy (clay) soils and can grow in heavy clay soil.
 It can grow it acid, neutral and alkaline soils, as well as shade or semi-shade.
 It requires moist soil.
Thespesia populnea, commonly known as the Indian tulip tree, Pacific rosewood, or Portia tree , is species of flowering plant in the mallow family, Malvaceae.
 It is a small tree or arborescent shrub that has a pantropical distribution, found on coasts around the world.
 However, the Portia tree is probably native only to the Old World, and may have originated in India.
 Nowadays, its wood is mainly used in making furniture because of its good ability to undergo carving.
 The wood from the tree was used by early Tamil people to make instruments in ancient Tamilakam.
 It is possibly indigenous to the Hawaiian Islands and elsewhere in the Pacific, but may have been spread by early Polynesians for its useful wood and bast fibres.
 The Portia tree reaches a height of 6 - tall and a trunk diameter of 20 - .
 It grows at elevations from sea level to 275 m in areas that receive 500 - of annual rainfall.
 The Portia tree is able to grow in the wide range of soil types that may be present in coastal environments, including soils derived from quartz (sand), limestone, and basalt; it favours neutral soils (pH of 6–7.4).
The red cabbage (purple-leaved varieties of "Brassica oleracea" Capitata Group) is a kind of cabbage, also known as purple cabbage, red kraut, or blue kraut after preparation.
 Its leaves are coloured dark red/purple.
 However, the plant changes its colour according to the pH value of the soil, due to a pigment belonging to anthocyanins.
 In acidic soils, the leaves grow more reddish, in neutral soils they will grow more purple, while an alkaline soil will produce rather greenish-yellow coloured cabbages.
 This explains the fact that the same plant is known by different colours in various regions.
 Furthermore, the juice of red cabbage can be used as a home-made pH indicator, turning red in acid and green/yellow in basic solutions.
 It can be found in Northern Europe, throughout the Americas, and in China.
Platystemon is a monotypic genus of flowering plants in the poppy family containing the single species Platystemon californicus, which is known by the common name creamcups.
 It is native to Oregon, California, Arizona, Utah and Baja California, and is found in open grasslands and sandy soils.
Carya aquatica (bitter pecan or water hickory) is a large tree, that can grow over 30 m tall of the Juglandaceae or walnut family.
 In the American South it is a dominant plant species found on clay flats and backwater areas near streams and rivers.
 The species reproduces aggressively both by seed and sprouts from roots and from stumps of cut trees.
 Water hickory is a major component of wetland forests now in the south eastern US, because of the selective cutting of more desirable tree species for the lumber industry.
 It is considered important in cleansing drainage waters since the plants slow water flow during flooding, allowing sediments to fall out of the water column.
 This tree species is tolerant of wet soils but grows best on well draining soils near rivers and other water ways.

Question: Do both Platystemon and Aulax grow in soils?
Answer: yes