August Color Appears at the Washington Park Arboretum

1)  Clerodendrum bungei C. bungei is a deciduous, suckering shrub producing upright shoots and opposite, ovate, toothed, dark green leaves tinged with purple when young.  Salverform, fragrant, dark pink flowers, each with five spreading lobes, are borne in rounded, terminal panicles from late summer to autumn.  Native to China and a member of the family Lamiaceae, this specimen is happily spreading around the south side of bed ‘G’ on Azalea Way. 

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“One is the loneliest number…”

The University of Washington Botanic Gardens is home to truly one of a kind plants.  In botanical nomenclature, a monotypic genus refers to the case where a genus and only a single species are described.  These plants are often “living fossils”, comprising the last living remnant of ancient lineages.  Many are also often in the IUCN Red List of Threatened Species. 

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July Color Appears at the Washington Park Arboretum

1)  Colutea orientalis                Bladder Senna This deciduous native of northern Iran has delicate bluish-green pinnate leaves. The orange flowers are followed by surprising translucent bladder-like fruit pods. You can find Colutea orientalis in the Legume Collection along Arboretum Drive. 2)  Hydrangea macrophylla  ‘Mme. Emile Mouillere’ Bigleaf Hydrangea Hydrangea macrophylla is native to Japan. This cultivar is an example of the Hortensia group – having mophead flowers. 

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Summer Arrives at the Washington Park Arboretum

1)  Cunninghamia lanceolata                (Chinese Fir) Bluish evergreen foliage contrasts nicely with its scaly bark. This evergreen tree from China is an important timber tree in its native area. In 1701, James Cunningham (one of the first European plant hunters to visit China) described and collected this tree. 2)  Hydrangea integrifolia                                                      (Evergreen Climbing Hydrangea) A vigorous, evergreen vine climbing to over 40 feet, on the trunk of a mature Douglas Fir. 

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The Wonderful World of Monocots

Monocotyledons, commonly referred to as monocots, are flowering plants whose seeds typically contain only one embryonic leaf, or cotyledon.  A quarter of the world’s known plants are monocots. They are the most economically important group of plants to humans today in agriculture, horticulture, forestry and fiber industries.  Here are a few samples of monocots in our plant collections. 1)  Allium schubertii                                                                            (Ornamental Tumbleweed Onion) Dried seed heads look like starry tumbleweeds or shooting star fireworks Located in the Soest Herbaceous Display Garden, bed 6 at the Center for Urban Horticulture 2)  Austroderia richardii syn Cortedaria r.                      

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Spring Pushes Forth at the Washington Park Arboretum

1)   Ostrya carpinifolia                Hop Hornbeam This small-to-medium-sized tree (40-50’) is native to southern Europe and southwestern Asia. The common name refers to the fruit which resembles the fruit of Humulus (Hops). Ostrya is from Greek, meaning “bone-like” in reference to the trees dense hard wood. Located north of East Foster Island Road, east of the Broadmoor entrance. 2)  Picea mariana ‘Doumetii’                Doumet Black Spruce This selection of Picea mariana is a popular slow-growing shrub with blue green needles and a dense conical growth habit. 

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May Colors Appear Just in Time for Mother's Day!

Happy Mother’s Day! 1)  Philadelphus coronarius Native to southeastern Europe and Asia Minor, this shrub is located within the Sorbus Collection. It is perhaps the best-known species of mock orange in gardens because of its sweet smell. The fragrance of its flowers is pleasing out-of-doors, but may become too strong if the plants are numerous or near sitting room windows. Philadelphus is a member of the plant family, Hydrangeaceae. 

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"Story Time" at the Washington Park Arboretum

The stories of people and plants are intricately intertwined.  The plants of the University of Washington Botanic Gardens have many stories to tell, and here are just a few to wet your whistle.  Explore our website at to look up and locate plants in the Arboretum and learn more of our stories. 1)  Abies grandis – Grand Fir                “Fir Above It All” This particular tree has witnessed the entire history of the Washington Park Arboretum.  

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April Color Appears at the Washington Park Arboretum

1)  Acer mandshuricum                Manchurian Maple The Manchurian Maple is native from Eastern Siberia into China and strongly resembles Acer griseum and Acer triflorum. This species is located in the Asian Maples Collection. 2)  Distylium racemosum                Isu Tree The flowers of Distylium racemosum are petalless, but have attractive red calyces (whorl of sepals) and purple stamens. The Isu tree is native to southern Japan, but can be found in the Witt Winter Garden and in our Hamamelidaceae Collection, east of Arboretum Drive near the Pacific Connections gardens. 

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