Variegated Asian Star Jasmine. Excellent evergreen ground cover with playful foliage that looks great year round. Lovely entire leaves are spaced and outlined in cream. Great contrast to the sage green leaf interior. Trailing ground cover (occasionally it can rise up to be a vine- in windfree locations with support) but mainly its value is a year round showy and consistent look. Mounding and trailing it will root into the ground when it feels like it. To 10″ tall and 3′ wide as a ground cover. To 10′ tall as a vine. Full sun to dense shade in rich, well drained soil. But it adapts to harsher sites if given regular water. Excellent under trees, shrubs. Dense enough to discourage weeds. Very cold and drought tolerant. Seldom blooms. Moderate deer resistance. This and all Trachelsospermum asiaticum have two distinct forms of foliage. Juvenile and adult. Juvenile foliage is associated with long trailing and vining material. In wind free, still locations it can rise up as vine and thats when it becomes adult. This plant ONLY BLOOMS ON ADULT foliage. So, that is one reason you seldom see flowers on Asian star jasmine. Over time adult foliage will appear on ground covers. Its less vining and more bushy. Again, until adult foliage forms there will be no flowers.
Biome: Dry Shade
Dry shade offers a particular challenge to PNW gardeners. In fact, it can be the hardest location to satisfactorily grow plants. Many gardeners have dry shade, a tall canopy of Douglas Fir or Oregon White Oak or even neighborhood street trees that can conspire to rob plants not only of light but water as well. And to complicate matters, the more you irrigate dry shade near trees the more tree roots you get and the more competition for your lovelies. The solution is to depend on plants that have these three adaptations: dry tolerance, root competition, low light conditions.
We’ve amassed a list of plants that really will thrive in these conditions. A good deal of these plants are native to the forest understory in Asia, they are built for serious competition with Bamboo. Many of our very best dry shade plants are from the Pacific Northwest and already inhabit dry woods. Invite these plants into your garden, they play an important role.
Prepare the soil as you would any rich perennial border. Add and incorporate compost and mulch. Give each plant a handful of all organic fertilizer to speed root growth and establishment and water faithfully for the first season. In these conditions an annual application of mulch is not obscene and will reap great rewards. In time you can water much more infrequently.
Climate Adapted Plants for Gardeners in the PNW
Trachelospermum jasminoides
Not a true Jasmine at all but Star Jasmine is a classic summer blooming evergreen vine in our region. One of the most popular vines and rightly so with its clouds of ivory colored propeller shaped sweetly fragrant flowers for all of summer. Twining vine, provide support- easily guided with the help of #4 gauge copper wire. It has the enviable trait of clothing itself to the ground in evergreen foliage- seldom has bare knees. Full sun to quite a bit of shade, including dry shade. To 12′ tall and 4′ wide in 6 years. Cold hardy to the single digits when established. Can be slightly tender when vines are young- hence the myth that it is not hardy. Regular water in summer speeds growth measurably and should be applied for the first few years. Blooms on wood from the current season. Prune before or after blooming. In warmer climates this vine is only a spring bloomer. In our milder summers with cooler overnight lows in summer it spurs Star Jasmine to bloom for all of our summer. Lucky us. Moderate deer resistance. Drought adapted with age. See below- trained as a free standing hedge in Laurelhurst. Kind of cool.
Trachelospermum jasminoides ‘Madison’
Reputed to be a hardier form of Star Jasmine, we really haven’t witnessed that. It seems just as hardy as the commonly grown clone. But it has several important differences. The large deep green leaves are conspicuously convex and thick. In June to September it alights with tons of ivory colored sweetly fragrant pinwheel shaped flowers. These are slightly smaller but come in such fragrant abundance that it doesn’t seem to matter. Evergreen from the base to the top which is nice. No bare knees. Full sun to quite a bit of shade in rich, well drained soil. Summer water speeds both growth and early establishment. Then light regular summer water. Moderate deer resistance. Twining to 15′ provide support. Fences, pergolas.
Trachelospermum jasminoides ‘Variegatum’
Nice form of star jasmine with large sage green leaves edged in cream. New growth emerges a very pretty pink. From June to August a continuous supply of clusters of sweetly fragrant ivory flowers. To 12′ tall and twining. Provide sturdy support. A nice attribute of Star Jasmines is their habit of keeping their foliage densely to the ground- never any bare knees. Takes full sun to quite a bit of shade- and still blooms. Slightly more tender than the species it requires a protected location- against a wall is ideal. Regular summer water speeds growth and this intensifies the re-blooming. Evergreen. Moderate deer resistance.
Trachelospermum mandianum
The apricot hued flowers of this Star Jasmine species are not the only difference in this elegant evergreen vine. The fragrance is different too with much more of a balmy citrus scent. Vigorous twining vine for part shade. Provide sturdy support. Very cold hardy and permanent. To 14′ tall and 8′ wide on trellis. Possible to use it as a small scale ground cover. Tolerates full sun but with some leaf discoloration. Regular summer water in well drained soil. Occasionally at the end of the season this species will form twin bean seed pods which are showy as well. Blooms earlier than Star Jasmine and finishes later as well. Evergreen foliage is light yellow green- lighter than other species of Star Jasmine. Moderate deer resistance.
Tricyrtis ‘Spotted Toad’
Toad lilies are the joy of late summer into autumn in the shade garden. This tall growing selection has leaves that are conspicuously spotted with maroon dots. In August to October 20″ stems support multiple orchid-like flowers. The flowers have three petals heavily marked with purple/blue dots. Very pretty. Surprisingly its a nice cut flower. Forms a spreading clump in time. Rich, moisture retentive soil in part shade to shade. It has the nice habit of winding through other plants and the cheery exotic flowers will show up quite far from the source. Very easy long lived perennial. Regular summer water. Avoid hot sun which will scorch the leaves. Completely deciduous in winter. Adapts to dry shade when established.
Trillium kurabayashii
One of Oregon’s greatest wildflowers. This native of the Siskiyous and the SW part of the state makes an outstanding garden plant. Ours are divisions from well marked leaves and flowers with a deep maroon/black hue. To 18″ tall in bloom it responds readily to rich, humus filled soil with regular summer water. In very dry conditions it will go happily summer dormant. And it usually does anyway by the end of the hot season. The black and green leaves are dramatic but a great collar to the tall upright dark flowers. Blooms appear in Portland in April/May and last for weeks. Part shade to shade- avoid blasting hot sun- it will grow in sun but go dormant very quickly. Roots very deep into the ground- difficult to move once established so pick its home carefully. Multiplies into a substantial patch with good care. One of our favorite native wildflowers. Limited quantities. Oregon native plant.
Vaccinium ovatum
Evergreen huckleberry is a fantastic native broadleaf shrub. It is well adapted to shady sites and will accept full sun with regular irrigation. Well established shrubs require less water. Rich, humusy woodland soil is its favorite haunt and it will grow moderately fast to a rounded outline of 8′ tall and 6′ wide. The new growth is a beautiful salmon pink before changing to deep green. In spring and early summer small white urn shaped flowers are pretty and transform into tasty black fruits in autumn. Amazing in muffins, pies.It has an interesting natural distribution along the immediate coast in most of Oregon but veering inland at Douglas County to almost the Cascade foothills. In Puget Sound it seems to be most prominent within sight of salt water. Easy to grow good garden plant. Oregon native plant.
Vancouveria chrysantha
Rare perennial Siskiyou Inside-out-Flower is a much more drought tolerant version of our locally native Vancouveria hexandra (Inside out flower). This yellow flowered species tolerates extreme dry shade and colonizes even compacted dry soils to create a handsome ground cover. The delicate looking interestingly shaped leaves create a soft mound of shapes in cool green and edged slightly in red. In April-June 20″ wiry spikes suspend small downward pointing flowers- they appear to float above the foliage reminding me of a group of fireflies. (Wish we had those). Mostly evergreen if temperatures stay above about 15ºF. Basically this is our version of Epimedium (to which it is related) but with more tolerance for summer drought. To 8″ tall and spreading to several feet wide in richer, moisture retentive soil. Light summer water increases growth. This is an extraordinarily elegant native that should find a happy home in gardens too. Part shade to full shade. Not bothered by pests. Excellent perennial under large shrubs or within tree roots. In the wild it is the understory plant to Arctostaphylos, Rhododendron, Vaccinium, Notholithocarpus densiflorus var. echinoides. Associate perennials were Oxalis oreganus and Mianthemum as well as viola semperivrens- Redwood violet. Easy community to replicate in your garden. Oregon native plant.
Vancouveria hexandra
Inside-Out-Flower is a commonly seen terrestrial component in dry to moderately moist woodlands in our region. The duck foot shaped leaves are conspicuous and pretty and in late spring to mid-summer a continuous supply of dainty downward pointing white flowers. Spreads in gardens very well in enriched soil with regular summer water where it will quickly assume the role of an intertwining ground cover. Winter deciduous- un-like its close and much more drought adapted relative Vancouveria chrysantha (Yellow inside-out-flower, Siskiyou Vancouveria). This perennial is perfect for life among shrubs or mixing with other woodland perennials in part shade to shade. Adapts well to garden culture and thrives on regular summer irrigation. Locally native in the city of Portland. To 10″ tall and spreading. Some deer resistance. Oregon native plant.