When it came to dreaming up place names, California’s gold rush prospectors had a matter-of-fact approach: Whiskeytown, Rough and Ready, and Happy Camp, for example. The boom-and-bust towns and rugged landscape clearly provided a rich if rather literal source of inspiration. And then, of course, there’s Death Valley.
Twenty wagon-loads of prospectors and their families, today known as the Death Valley ’49ers (as they began their journey in 1849), headed west in search of a short cut but they got lost and became weak with hunger. Desperate for food, they killed some of their emaciated oxen and set fire to their wagons to cook the meat at a spot now known, of course, as Burned Wagons. Legend has it that as part of the group were eventually rescued and left the valley, one of their number looked back and said, “Goodbye, Death Valley”. In fact, just one of the lost ’49ers died in the valley – an elderly man – but whether the legend is true or not, the name stuck.
What they couldn’t have known is that this wasn’t any old bleak and inhospitable valley; Death Valley is the driest place in North America, and at 86m (282ft) below sea level is also the lowest. It holds the record for the hottest temperature on Earth, 56.7C (134F), recorded at – I’m sure you’re getting the feel for this now – Furnace Creek in 1913. In 1996, summer temperatures stayed above 120F for 40 days. But in spite of the forbidding name and inhospitable records, Death Valley has the capacity to transform into one of the most extraordinary floral events on the planet.
Located on the border of California and Nevada and occupying around 3,000 sq miles, Death Valley is hemmed in by the Panamint and Sierra Nevada mountains. They and the low, relatively flat surface of the valley create an effect similar to a convection oven. The surface of the valley heats the air above, which rises, is cooled by the mountains, settles back to the valley floor and is heated again, becoming superheated. The landscape ranges from ochre hillsides that glow in the sunset, salt pans, sagebrush scrub and sand dunes straight out of Star Wars – George Lucas used Death Valley’s terrain for location shooting.
Given the right conditions, the dry flats and hillsides become carpeted with swaths of colourful wildflowers. The showiest flowers are often shortlived annuals. So fleeting is their time on Earth, they are usually referred to as ephemerals, and their life cycle can be as brief as a matter of days. This is a survival strategy for coping with the desert conditions. By living fast and dying young, they have a chance to complete their mission – to flower and then to produce the seed that ensures the survival of the species – before the heat fries their foliage and flowers, or hungry animals get to them. When they do bloom, the entire valley seems to blossom as it is filled with pollinating butterflies, hummingbirds, bees and moths. The flowers and pollinators in turn provide a food bonanza for the resident wildlife, which ranges from a species of tortoise, numerous bats, more than 30 different lizards and snakes, and species such as the roadrunner, bighorn sheep and Mojave sidewinder.
The ideal weather scenario for a bumper wildflower year starts with a rainstorm in September or October. This is by no means a common occurrence; the average rainfall for those months is just 0.4cm and 0.3cm respectively. A good soaking of the soil surface ensures the seeds’ protective coating, which otherwise inhibits germination, is broken down and washed off. Following germination, further regular, gentle rainfall is required through winter and spring to keep the delicate seedlings growing. This only happens in years when the rainfall is higher than average. Strong, drying winds that are common in the valley can quickly desiccate young seedlings and kill them before they have a chance to bloom, so these need to be absent too. If the plants make it through all of that, and avoid being eaten, then they will make it into flower. Needless to say the really big “shows” of flowers are a once-in-a-decade-or-two event.
Flowering begins at the lowest elevations in early spring, and the literal place naming applies just as readily to the flowers. From mid-February to mid-April, there are carpets of Desert Gold (Geraea canescens), highlighted with purple Bigelow’s Monkeyflower (Mimulus bigelovii), and the blue-purple of Phacelia calthifolia and Phacelia crenulata. In the best years, the Desert Gold does exactly that, turning miles of flatlands into sheets of gold. As spring unwinds, wildflowers fade and new ones bloom at the higher, cooler levels of the valleys and canyons. Desert dandelion (Malacothrix glabrata), with stiff flowers, soft yellow at the centre fading to white, and the erect yellow blooms of Prince’s Plume (Stanleya pinnata) grow in lower densities than the low-level wildflowers. The gloriously intense red Desert Paintbrush (Castilleja chromosa) is a gem that can only be enjoyed in the wild. It is a hemiparasite, using other plants to obtain water and nutrients, making garden cultivation almost impossible.
Finally, the high-level plants come into bloom, those growing above 5,000ft in the pinyon and juniper woodlands and on the mountainsides. The flowers seem more familiar here, with a species of penstemon (Penstemon floridus austinii) and the unashamedly named Magnificent lupine (Lupinus magnificus). If you’re lucky enough to see it, the Desert Mariposa (Calochortus kennedyi), is one of the highlights, a lily with supremely showy yellow or orange flowers that has resisted all attempts to grow in garden surroundings.
Many of these desert specialists can be seen elsewhere in southwestern America but at Death Valley the transformation to flower-filled landscape seems much more intense. Standing in the hairdryer heat, surrounded by acres of flowers and in one of those rare places in the developed world where one can experience near total silence, is unforgettable. Perhaps, if the ’49ers had been lost in spring, we’d know it by a very different name.
Matthew Wilson is managing director of Clifton Nurseries, London
How to grow desert flowers
Desert wildflower adaptations can make some of them unsuitable or undesirable for gardens. Those that work in a xerophytic or gravel gardens have less specialised needs, provided the annual rainfall is low – ideally less than 400mm – and light levels are high, with very fast-draining soil.
Desert Purple Sage (Salvia dorrii) is a handsome shrub, low-growing with silvery aromatic foliage and blue flowers with purple bracts.
Desert Globeflower (Sphaeralcea ambigua) produces a burst of flowers in spring and periodically through summer.
Seed of Magnificent Lupine is hard to find but there are desert lupins that can be grown from seed, including the Texas Bluebonnet.
In temperate climates there are plenty of desert fringe plants that will create the right mood.
Berkheya purpurea is a thistle with large mauve or purple flowers held above a rosette of tough-looking foliage.
Another is Morina longifolia, from Kashmir and Bhutan, with spiny leaves and tubular blooms with a delicate citrus fragrance.
From the desert margins and rocky coastal hills is the state flower of California, Eschscholzia californica. Easy to grow from seed, it forms self-sown colonies that weave happily through features such as gravel drives and paths.