Snowbells

Styrax

A genus of very attractive spring flowering trees that generally prefer a cool, moist climate with cold but not frigid winters. They grow best in acid to neutral, fertile, well drained soil with lots of humus in sun or partial shade on a humid site sheltered from excessive wind. Snowbells enjoy an acidic ,deep, organic mulch of pine needles or shredded oak leaves. Sounds complicated but is really your average woodland understory conditions which is where these trees typically grow in the wild. The roots grow deep so shallow soil may not be acceptable to the Snowbells. They also do not enjoy root disturbance and are best transplanted while small.
Most Snowbells should be trained to a single leader and can be thinned and limbed up in March.
Propagation is from seed which usually needs stratification to easily germinate or by summer softwood cuttings taken on the cultivars.

Styrax americanus ( American Snowbell )
A fast growing, rounded, deciduous, small tree, up to 20 x 15 feet, that is native to the southeast U.S. ( from southeastern Missouri to southern Indiana to central Virginia; south to eastern Texas to central Florida...it is absent from Appalachian Region...a separate population occurs in Indiana counties along Lake Michigan ). Some records include: 2 years - 5 feet from cuttings; largest on record - 32 x 20 feet with a trunk diameter of 4 inches. Typically in nursery production, it takes 2 years to grow a salable 1 gallon size plant. A spring seedling has been known to reach 4 feet in height in a 1 gallon container during the first growing season. It makes a great tree for the patio.
The toothed, elliptical leaves, up to 4 x 1.5 inches in size, are bright green, turning to pale yellow during fall.
The pendulous flower clusters carry up to 4 white flowers in late spring.
The branches are covered in golden downy at first eventually becoming gray-brown. The gray bark is smooth on younger trees, becoming fissured with age.
Hardy zones 4a to 9, hardier than expected considering its natural range, it is hardy north to Michigan. It prefers full sun to partial shade on moist, fertile, acidic to neutral, well drained soil though is tolerant of flooding as well as moderate drought. Transplanting should be done during early spring.

* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken on Apr 17 2016 @ U.S. National Arboretum, DC

* photo taken on Apr 23 2017 @ Brookside Gardens, Wheaton, MD

'Kankanee Form'
The hardiest clone ( zone 4b ), it comes from a disjunct population found in the wild in southern Illinois.

Styrax benzoin
A small tree to 30 x 20 ( rarely 40 ) feet that is native to rainforest on the island of Sumatra in southeast Asia.
The oval leaves, up to 6 inches in length, are glossy mid-green above, white beneath.
The fragrant, white flowers are borne on panicles.
Hardy zones 9 to 12 ( estimate ).

* excellent article found on internet
http://tropicalplantbook.com/aromatic_plants/pages/benzoin.htm

Styrax confusus ( Chinese Snowbell )
A moderate to fast growing, small tree, that is native to mountains of central China at around 2000 meters in elevation. Some records include: 3 years - 9 x 4 feet; 12 years - 16.5 feet; largest on record - 27 feet with a trunk diameter of 5 inches.
The leathery, oblong to elliptical leaves, up to 5.5 x 2.8 inches in size, are very glossy mid-green.
The white flowers, up to 0.8 inches, are borne 3 to 8 on clusters up to 4 inches in length. They are borne during late spring, a week or so after Styrax japonicus. The petals are distinctly curved.
They are followed by rounded capsules up to 0.6 inches across.
The attractive bark is smooth.
Hardy north to zone 5 to 8. It is heat tolerant and thrives as far south as Arkansas to the Carolinas.

Styrax dasyanthus ( Smooth Styrax )
Also called Silvery Snowbell. A fast growing, small to medium-sized, deciduous tree, that is similar to Styrax japonica but faster growing. Some records include: fastest growth rate - 4 feet; largest on record - 66 x 25 feet with a trunk diameter of 1 foot. It is native to central China.
The ovate to elliptical leaves, up to 7 x 3 inches in size, are very glossy deep green.
Hardy zones 4 to 8. It is tolerant of flooding.


* photo taken on May 16 2010 @ Cylburn Arboretum, Baltimore, MD

* photos taken on 4th of July 2010 @ U.S. National Arboretum, D.C.


* photos taken on Aug 30 2021 @ U.S. National Arboretum, Washington, DC

Styrax formosanus ( Formosan Snowbell )
A subtropical member of the Snowbells that is native to southeastern China and Taiwan. A moderate growing, deciduous, large shrub or small tree, it can reach up to 23 feet with a trunk diameter of 4 inches in 15 years. Older plants become slow growing and the maximum eventual size wouldn't be much more, possibly 33 x 20 feet.
The papery, toothed, obovate to elliptical leaves are up to 2.8 x 1 inch in size. The attractive foliage is very glossy bright green, later turning to deep green.
The showy, abundant, white flowers, up to 0.6 inches in size, are borne 3 to 5 on clusters up to 1.8 inches in length.
Hardy zones 6b or 7 to 10 ( estimate for seed source collected at 7500 + feet in mountains in Taiwan...lowland seed may not be hardy north of 8b ). It thrives in full sun to partial shade on moist, acidic to neutreal, fertile, well drained soil.

Styrax glabrescens ( Mexican Snowbell )
Also called Styrax pilosus. A fast growing, medium-sized tree, reaching up to 100 feet, that is native to oak-pine and cloud forests in Queretaro and Veracruz states in Mexico, south to Costa Rica. It is related to Styrax grandiflora but has larger leaves and flowers.
The smooth-edged to lightly-toothed, ovate leaves are up to 8 ( rarely over 5.5 x 4 ) inches in size. The foliage is mid-green.
The white flowers are borne on racemes during winter in its natural range, late spring in the eastern U.S.
The bark is shedded, often peeling off long strips.
Hardy zones 7b to 9, one tree survived at Raulston Arboretum in Raleigh, North Carolina before perishing during a late freeze. It is easily propagated from softwood cuttings. It is extrrmely rare in cultivation but deserves much wider use.

Styrax grandifolius ( Big Leafed Snowbell )
A moderate growing, small tree native to southeastern U.S. ( Oklahoma / Arkansas border to southern Indiana to southeast Ohio to central Virginia; south to the Gulf Coast ) reaching up to 20 feet. Some records include: fastest recorded growth rate - 3 feet; largest on record - 50 x 15 feet with a trunk diameter of 1 foot. In its native range it can be found in forest understorys. It is now extinct in Ohio, there were formerly multiple confirmed reports up until 1939 of it growing on a limestone ridge near Buchtel in Athens County though the site has since been destroyed. It is also endangered in Illinois and Indiana.
The finely-toothed, broadly-oval leaves, up to 8 x 5 ( rarely over 5 x 3 ) inches in size, are deep green above, downy-white beneath.
The bell-shaped, white flowers, up to an inch in size, are borne in racemes up to 8 inches in length during late spring.
Dry, oval fruits up to 0.3 inches in size follow the flowers and ripen in early fall.
The zigzagged young stems have a yellowish downy coating.
The bark is smooth, red-brown to gray brown.
Hardy zones 6 to 10 ( use far northern seed source only in zone 6 ). Spreads moderately fast by root suckers but is not grown from cuttings. A classy native plant that should be planted much more.

* photo taken on Aug 5 2017 @ Brookside Gardens, Wheaton, MD

Styrax hemsleyanus ( Hemsley Snowbell )
A moderate growing, small tree native to mountain slopes in central China, reaching around 20 feet. Some records include: fastest recorded growth rate - 3 feet; 5 years - 10 x 7 feet; largest on record - 50 feet in height with a trunk diameter of 16 inches.
The heavily-textured, rounded leaves, up to 9 x 6 ( rarely over 5 x 2.5 ) inches in size, are light green above, finely-hairy beneath.
The white flowers, up to 1 inch long, are borne on racemes up to 8 inches in length, during late spring.
They are followed by gray, round, berrylike fruits up to 0.5 inches in size, enclosing a single seed.
The bark is gray and smooth.
Hardy zones 5 to 9, it is more drought tolerant than S. obassia but still prefers a moist site.

Styrax hookeri ( Yunnan Snowbell )
Also called Styrax grandiflorus and Styrax yunnanensis. A very rare, small, deciduous tree, reaching a maximum height of 33 feet with a trunk diameter of 1 foot. It is native from Nepal to southern China and Taiwan; south to northeast India to Burma.
The bark is dark gray.
The narrowly oblong to elliptical leaves, up to 3.5 x 1.5 inches in size, are glossy bright green.
The showy, pure white flowers, up to 1.2 inches in size, are borne during late spring.
Hardy zones 8 to 9, preferring maritime climates with mild winters and cool summers. Carefully selected seed source from high elevations in China may have potential for the southeastern U.S.

Styrax japonicus ( Japanese Snowbell )
A medium-sized, deciduous tree, native to most of southern and eastern China, Korea and much of Japan, reaching up to 40 x 40 feet in 20 years and to an eventual maximum size of 70 x 40 x 3 feet ( usually half that ). One exceptionally large tree of almost 3 foot trunk diameter is known to grow at 11 Old Windy Bush Road in New Hope, Pennsylvania, another very large tree grows at Longwood Gardens nearby. Some additional records include: 5 years - 11.5 feet with a trunk diameter of 3 inches.
The finely-toothed, oval leaves are up to 4 x 2.3 inches in size. The glossy deep green foliage turns to yellow or red very late in the fall.
The white flowers, up to 0.5 inches in size, are borne on short, pendulous clusters during late spring.
They are followed by hard, gray, berrylike fruits up to 0.5 inch in size that encase as single seed.
The dark purplish-brown bark is smooth at first, later becoming fissured.
Hardy zones 5 to 8.

* photos taken @ U.S. National Arboretum on Feb 2009


* photos taken on April 15 2010 in Columbia, MD

* photos taken @ U.S. National Arboretum on May 1 2010






* photo taken on May 16 2010 @ Cylburn Arboretum, Baltimore, MD


* photos taken on July 17 2010 @ Morris Arboretum, Philly, PA





* photos taken on May 7 2014 @ London Town Gardens, Edgewater, MD

* photo taken on Feb 8 2014 @ U.S. National Arboretum, DC

* photos taken on Nov 19 2016 @ London Town Gardens, Edgewater, MD

* photo taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photos taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

'Carillon'
Strongly weeping, reaching to 25 feet tall with a trunk diameter up to 2 ft. Some records include: 10 years - 10 feet.

* photo taken on May 6 2010 @ Brookside Gardens, Wheaton, MD


* photo taken on May 8 2010 @ U.S. National Arboretum, D.C.

* photo taken on Apr 23 2017 @ Brookside Gardens, Wheaton, MD

* photo taken on Aug 5 2017 @ Brookside Gardens, Wheaton, MD

* photos taken on Nov 10 2020 @ Brookside Gardens, Wheaton, MD

* photo taken on Aug 1 2022 in Brookside Gardens, Wheaton, MD

'Emerald Pagoda'
Very fast growing with double the typical growth rate. It can grow at a rate up to 4 feet per year when young. Its leaves are also 3 times the average size, up to 8 x 4 inches. They are dark green, thick, leathery and looking quite tropical.
The flowers are white and also large, up to 2 inches in size.
It is also far more heat tolerant than regular Styrax japonica and grows with a strong central leader.
It is native to Sohuksan Island in Korea but is now extinct in the wild.

* photo taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

'Evening Light'
A very attractive form, reaching up to 5 x 2.5 feet in 4 years, to 12 x 5 feet in 10 years, eventually to around 15 x 8 feet. It is a vigorous yet dwarf form that matures much smaller than regular Styrax japonica.
The foliage is glossy deep purple, turning to deep green by late summer. The elliptical leaves are up to 3 x 1.5 inches in size.
The pure white flowers, up to 1 inch wide, during late spring, provides stunning contrast with the foliage. It sometimes reblooms during early autumn.
Hardy zones 5 to 9

* patent photos

Variety 'Fargesii'
Intermediate betweem 'Emerald Pagoda and regular Styrax japonica. It has deep green foliage and is fast growing, reaching about 18 x 15 feet in only 10 years.

'Fragrant Fountain'
A fast growing, strongly-weeping form, reaching up to 9 x 5 feet in 8 years, to 12 x 8 feet in 20 years, eventually larger.
The foliage is glossy deep green. The obovate leaves are up to 3 x 1.8 inches in size.
The abundant flowers are white.
Hardy zones 6 to 8

* patent photo

'Issai'
Faster growing to 30 x 30 feet with an upright form and heavy crops of white spring flowers.
The foliage is larger than that of the species.

* photos taken on Oct 14 2015 in Baltimore Co., MD

'Marley's Pink'
A fast growing, strongly-weeping form, reaching up to 9 x 5 feet in 8 years, to 12 x 8 feet in 20 years, eventually larger.
The foliage is glossy deep green, turning to bright yellow during autumn. The obovate leaves are up to 4 x 2.5 inches in size.
The abundant flowers are pink.
Hardy zones 5a to 8

* patent photos

'Martin's Red Star'
Nearly identical to 'Evening Light' but very fast growing, almost double the growth rate.

'Pink Chimes'
Same as regular Styrax japonica but with pink flowers.

* photos taken on May 6 2010 @ Brookside Gardens, Wheaton, MD




* photos taken on Nov 10 2020 @ Brookside Gardens, Wheaton, MD

'Prystine Spire'
Strongly-upright and columnar in habit, reaching up to 12 x 4 feet with a trunk diameter of 2" in 5 years, to 25 x 8 feet in 20 years, eventually more.
The leathery foliage is glossy deep green. The elliptical leaves average 2.3 x 1.2" in size.
The abundant flowers are white.
Hardy zones 5 to 8. It thrives in the southeast.

* patent photo

'Snowcone'
Resistant to twig dieback found in the species. This heat tolerant selection has grown well in Texas.

* photos taken on June 18 2013 in Columbia, MD

* photos taken on June 1 2014 in Columbia, MD

* photo taken on Nov 4 2015 in Columbia, MD

* photo taken on Jun 2 2016 in Columbia, MD

* photo taken on Sep 23 2016 in Columbia, MD

* photo taken on Aug 21 2017 in Columbia, MD

* photos taken on May 20 2019 in Columbia, MD

* photos taken on Sep 4 2020 in Columbia, MD

* photos taken on May 23 2021 in Columbia, MD

* photo taken on Oct 2 2023 in Ellicott City, MD

Styrax obassia ( Bigleaf Styrax )
Also called Fragrant Snowbell. A moderate growing, medium-sized tree, that is native to northern China, Korea and much of Japan. Some records include: 25 years - 35 x 34 feet with a trunk diameter of 0.9 feet; largest on record - 60 x 50 feet with a trunk diameter of 1.5 feet. One tree already grew to 45 x 35 x 1 ft. in Mansfield, CT, one nearly as large grows at Longwood Gardens near Philly.
The rounded leaves are up to 10 x 11 inches in size though usually smaller. The tropical looking foliage is deep green above, downy blue-green beneath. The foliage is late to appear during spring and turns to yellow during autumn.
It has rounded and tropical looking 10 x 11 inch leaves which are dark green above and downy blue green below. Typically late leafing out in spring though the foliage remains late in fall and turns to yellow.
The abundant, fragrant, white flowers, up to 1 inch across, are borne on clusters up to 10 inches in length, during late spring.
The attractive light gray bark is smooth at first. later becoming vertically fissured.
Hardy zones 4 to 9 ( seed source from Manchuria should be used in zones 4 & 5 ), it is heat tolerant. The Bigleaf Styrax does not enjoy clay. It prefers moist but well drained soil and the foliage may turn an unhealthy pale green if moisture is deficient.

* photos taken on March 28 2010 @ U.S. National Arboretum, D.C.


* photos taken on April 18 2010 @ U.S. National Arboretum, DC


* photo taken on May 6 2010 @ Brookside Gardens, Wheaton, MD


* photos taken on May 8 2010 @ U.S. National Arboretum, D.C.








* photo taken on July 17 2010 @ Morris Arboretum, Philly, PA

* photo taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photo taken on July 27 2019 in Columbia, MD

* photos taken on July 13 2021 @ Hershey Gardens, Hershey PA

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photos taken on Aug 30 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on June 19 2023 @ Hershey Gardens, Hershey, PA

* photo of unknown internet source

Styrax odoratissimus ( Sweet Styrax )
Also called S. veitchiorum. A rare single trunked tree native to from shaded ravines in southwestern to south-central China. It can reach 17 feet in 15 years and eventually up to 33 x 30 feet with a trunk diameter of 8 inches.
The striking foliage is similar to Styrax obassia but is heart shaped and very deep green. The lance-shaped leaves, up to 6 x 3 inches, are large for a Snowbell.
The white flowers are very fragrant.
The trunk is gray and smooth.
Hardy zones 6 to 9

Styrax officinalis ( Storax )
A moderate growing, small tree that is native to southern Europe, western Asia and California ( San Luis Obispo to San Diego counties ). It can reach up to 23 x 10 feet with a trunk diameter of 10 inches, though trees as tall as 50 x 25 feet with a trunk diameters of 2 feet has been reported. The California subspecies if has recently been separated into a separate species called Styrax redivivus by many botanists.
The smooth-edged, oval to rounded leaves are up to 4 x 3 inches in size. The foliage is deep green above, grayish-white beneath; turning to yellow during autumn.
The fragrant, white, bell-shaped flowers, up to 0.8 inches wide, are borne on pendant clusters ( of 3 to 6 ) at the branch tips during late spring.
They are followed by a grayish drupe, up to 0.3 inches long.
The gray bark is smooth.
Hardy only zones 8 to 10 ( 7 for subsp redivivus of California ) in full sun to partial shade. It grows well in Mediterranean regions around the world, including coastal California. Styrax officinalis is tolerant of dry conditions unlike most of the Styrax.

* excellent photo link
http://commons.wikimedia.org/wiki/File:Styrax_officinalis_tree.JPG

Styrax platanifolius ( Sycamore Leaf Snowbell )
A deciduous, non-suckering, large shrub to small tree ( if trained ), reaching a maximum size of 20 x 12 ( rarely over 12 x 8 feet ), that is native to the Edwards Plateau in central Texas, south into northeastern Mexico ( valleys in the eastern Sierra Madre Oriental mountains in Neuvo Leon & Tamaulipas States ).
The toothed to lobed leaves, often resembling that of the American Sycamore in shape, are up to 5 x 4.5 ( rarely over 4 x 3 ) inches in size. The foliage is glossy deep green above, felted pale green to white beneath.
The showy, white flowers, up to 0.8 inches in length, are borne during late spring.
They are followed by hairy, rounded, capsules, up to 0.3 inches wide.
The bark is dark gray.
Hardy zones 8 to 9 in partial shade on well drained soil. It is rarely bothered by disease and is moderately drought tolerant and very tolerant of alkaline soils.

* photo taken by Clarence A. Rechenthin @ USDA-NRCS PLANTS Database

var texanus ( Texas Snowbell )
Similar, except with smooth-margined, broadly-ovate to rounded leaves.
It is endangered, with only 22 populations remaining in its native Edwards Plateau of Texas where it is found on river banks and in canyons.

Styrax portoricense ( Puerto Rican Snowbell )
An extremely rare ( endangered ), evergreen tree, reaching up to 66 feet in height, that is native to Puerto Rico.
The elliptical leaves, up to 4.7 x 2 inches in size, are very glossy, bright green.
The white, star-shaped flowers, up to 0.5 inches wide, are borne 6 or 7 per cluster.
Hardy zones 10 to 11.

* USDA archive

Styrax serrulatus
Typically a small tree to 40 feet that native from Bhutan to southern China to Taiwan; south to India, Burma, Leos, Thailand and Vietnam. Some records include: largest on record - 55 feet with a trunk diameter of 1 foot.
The finely-toothed, ovate or oblong leaves, up to 6 x 2.2 inches in size, are mid-green.
The white flowers, up to 0.5 inches, are borne in clusters during late spring.
They are followed by capsules up to 0.6 x 0.3 inches. Hardy zones 9 to 10 in subtropical climates.

Styrax suberifolius ( Cork Leaved Styrax )
A fast growing, rounded, medium-sized tree, reaching up to 65 feet, that is native to southern China & Taiwan; south to Burma and Vietnam. Some records include: 7 years - 27 feet.
The leathery, elliptical leaves, up to 7 x 3 inches in size, are very glossy bright green at first, turning to deep green above, white beneath. The foliage is the most attractive of all the Snowbells.
The hanging, white flowers, up to 0.6 inches across, are borne on many flowered panicles, up to 4.8 inches in length, during late spring.
They are followed by woolly, rounded seed capsules.
Hardy zones 8b to 10 ( estimate ) in full sun or partial shade on well drained soil and a site protected from wind.

Styrax tonkinensis ( Tonkin Styrax )
The largest tree of the Styrax family, with trees are large as 100 feet in height and 2 feet in diameter being recorded in its native southeast Asia and warmer parts of China. Very fast growing, it may reach as much as 82 feet in height with a trunk diameter of 9.5 inches in as little as 10 years, with growth rates as much as 10 feet being recorded.
The leaves are large for a Snowbell, up to 7 x 4 inches in size. The foliage is smooth bright green above, hairy whitish-green beneath.
Blooms heavily at a young age with fragrant, white, bell shaped flowers that emerge from cinnamon color buds.
Hardy north to zone 8, further testing is needed to determine zone 7

Styrax veitchii
A deciduous small tree, reaching a maximum height of 40 feet, that is native to China.
The ovate leaves, up to 5 x 2 inches, are mid-green.
The small, white flowers are borne on clusters up to 8 inches in length.
Hardy zones 6 to 8.

Styrax wilsoniii ( Wilson's Snowbell )
A moderate growing, bushy, deciduous, large shrub, reaching around 8 feet, that is native to western China. Some records include: 12 years - 15 x 15 feet; largest on record - 20 x 10 feet with a trunk diameter of 1 foot.
The oval to elliptic leaves, up to 4 inches in length, are deep green.
The very abundant, yellow-centered, white flowers are borne on pendent racemes during late spring.
The shoots are slender.
Hardy zones 5 to 8.

Styrax youngiae ( Young's Snowbell )
Also called Styrax platanifolius youngia. An extremely rare small tree that is native to the Davis Mountains in southwestern Texas and nearby northern Coahuila in Mexico. It was throught to be extinct and is extinct in Texas but a nearby Mexican population was recently discovered. It is different from Styrax platanifolius in that the foliage is hairy beneath.
The abundant showy flowers are white.
Hardy zones 7 to 9