Mules Ears are rare in cultivation. These cheery bold perennials make the transition of our wild flowers from spring into real summer. So named for its long leaves it forms very permanent spreading colonies in clay soils in habitat. The brilliant yellow sun flower blossoms rise up on sturdy stems directly from the ground. Each ebullient large flower is about 4″ across. Blooms appear from late April to early June. This plant usually finishes blooming just as summer drought commences. Its a memorable sight in wild meadows where it blooms simultaneously with native Rosa nutkana and Farewell to spring (Clarkia amoena var. lindleyi) and Giant blue eyed mary (Collinsia grandiflora). Wonderful cut flower and immediate and popular pollinator perennial. This plant was once very common in the Willamette Valley but civilization has immensely shrunk its native range. Good, long lived garden plant that goes summer dormant quickly after blooming has ended. The leaves turn gray and brittle and can easily be removed then. Give it a summer rest w/ little to no summer water once established. Full sun to very light shade. Water to establish its first season then none in subsequent years. Fun to grow and LONG lived. To 14″ in bloom forming a plant several feet across. Moderate deer resistance. Native to the Portland city limits. Oregon native plant
Biome: Western Native
Native is a relative term. Plants don’t follow political boundaries and in fact they cluster and move according to climate and to a lesser extent soils. Turns out for instance, that the climate of Portland is not too dissimilar from the middle elevations of the Sierra Nevada in California. And as the planet waxes and wanes through ice ages you’d be amazed at the distance plants migrate due to climate. In fact, if you went back in time 11,000 years ago in the middle of the last ice age the taxa composition of the Portland area was identical to what you currently find on the upper slopes of Mt. Hood at 6,000′. Cold, snow, montane with Mountain Hemlock, Engelmann Spruce, Lodgepole pine and Aspen. In reality plants are always on the move.
Between ice ages- the last interstadial
More relevant is our most recent interstadial, the warm period between ice ages that peaked around 6500 years ago. Then, perihelion (the sun’s closest axis to earth) occurred in the Northern Hemisphere summer increasing solar insolation (sun heat energy). Currently, perihelion occurs in winter (Jan. 5, 2020) over our continent and that somewhat cancels out the effect. This increased solar insolation during the interstadial did several things: First, it increased the annual temperatures to those we have only surpassed recently and it decreased precipitation and increased the length of the annual summer drought. During these warm periods there is a great shift in south to north flora movement. At the peak of the interstadial warm period the Eugene area most likely had a climate and flora composition of the Grants Pass area today. Portland likely had a climate and taxa somewhat similar to modern Roseburg. That would be a lot more Oaks and Madrone and much less Maple and Douglas Fir. This passage to the north of flora extends poleward and it is also during this period we see the intrusion of Pacific Madrone Arbutus menziesii and Quercus garryana Oregon white oak into British Columbia. Climate change is mimicking our warm interstadial so far. Species from the south are rapidly moving north- and faster all the time.
Broadening the description
So, we choose to list WESTERN NATIVES and not just Oregon Natives in one category. We should always include natives in our gardens. They are not only climate adapted, they give our gardens a regional identitand most importantly they support native fauna. And climate change adds complexity to the mix. Our planet will be heating up too fast for plants to migrate. That means that many will find the safest homes in our gardens. We seek out the most unusual natives. Our attempt to expand the palette rather than the six same species that are used (abused) over and over. By all means go native!
Climate Adapted Plants for Gardeners in the PNW
Yucca (nana) hermmaniae
Adorable and rugged little dwarf Yucca from southern Utah. Tight round quills are decorated with filaments on the leaf edges. Not a friendly guy and very slow growing. Forming spheres of spikes to 1′ across and multiplying to produce colonies with pups. Full sun and very well drained soil of average to poor fertility. Requires excellent air circulation- no crowding. Plants that are smooshed with little air circulation protest heavily and it then takes a while for recovery. Open and free in rock garden conditions produces the happiest plants. At home nestled with boulders or as a finer texture element with Agaves. In time it produces adorable and conical shaped hoods of flowers- a gnome wedding. Excellent in containers- open, well drained containers. Light summer water during hot weather seems to speed growth. Locate away from paths. Owwie. Strongly deer and rabbit resistant.
Yucca rostrata
Beaked Yucca does fantastically well in our climate and is one of the Yucca species that will form a dramatic trunk. Blue thin leaves radiate out in a perfectly round orb. Slowly rises to 8′ tall in our climate. Full hot all day sun in a warm position. Very well drained soil with light summer water during the hottest stretches to encourage growth. Occasionally, with age 4′ spikes appear holding large trusses of ivory flowers. Perfectly hardy to cold, way below 0ºF. Avoid cold wet sites- to really do well it needs heat and exposure. Not prone to bacterial leaf blight that affects other Yucca species. Good air circulation. Lives happily in large containers for eons. Focal point in many of the best gardens in our region. High deer resistance. Evergreen.