Miscellaneous Flashcards
Alleghany Serviceberry
Amelanchier laevis
Plant Description
Amelanchier laevis, or Allegheny Serviceberry, is a large shrub or small flowering tree, growing 15-25 feet high and 10-15 feet wide. It is adaptable to a wide variety of soil conditions, including almost constantly moist to drought. Although Dirr believes states that it will not perform well under stressful conditions, I have used them successfully as parking strip trees and they have performed admirably on very minimal water in poor soil. It naturally occurs in a multi-stemmed form, but is readily available in tree form as well. The form is open and rounded.
The bark on new growth is reddish-brown and then turns to a gray color. When mature, it has delicate ridges that make it look like the stems are striped. The stems are slender, and even mature trees have comparably small branches.
The leaf is elliptic or ovate, 1 1/4 - 3 inches long with a subcordate base and arranged alternately on the stem. The margin of the leaf is finely serrated. The leaves are a medium to dark green color and often are tinged a dark reddish color when they emerge in the spring. New leaves are pubescent. In the fall the leaves turn a bright orange or red fall color, in my opinion some of the best quality color on a tree or shrub.
In the spring, the tree blooms profusely with small white blossoms appearing on 2-4 inch long hanging racemes. It would be more showy if the tree had a more dense canopy. Small bluish-black pome fruit forms on the tree during the summer and ripens by mid-summer. The fruit is edible and tastes similar to blueberry. If you don’t harvest the fruit it is persistent, but the birds will pick the tree clean before any fruit could drop anyway.
Landscape Use
Serviceberry can be used in any number of settings. They make an excellent choice as a lawn tree or accent tree because of their multi-season interest. I have used them as street trees and find that they perform admirably and attract a lot of interest from the neighbors.
Points of Interest
Serviceberry is susceptible to fireblight and cedar serviceberry rust. Most of the popular cultivars have proven to have very little disease problem.
Notable Cultivars
Spring Flurry: The best cultivar of Amelanchier for street trees. It has a an upright oval form with a strong central leader and dense branching habit. The fall color is bright orange.
Amelanchier x grandiflora - Autumn Brilliance: A hardy Serviceberry with a strong branching habit and good upright rounded form. It has exceptional bright red fall color. Grows 20 feet high and 15 feet wide.
Butterfly Bush
Buddleia davidii
Plant Description
Buddleia davidii, or Butterfly Bush, is a medium to large woody shrub that acts like an herbacious perennial in colder climates. It grows 10-15 (only 5-12 feet in Utah) feet tall and 5-10 feet wide. It has long, arching canes that give it a fountain shape. It is a vigorous grower that has proven to be invasive in other parts of the country, so much so that the State of Oregon has placed it on its list of invasive weeds - causing a sudden supply shortage throughout the west as nurseries in Oregon have stopped growing it. It should be planted in full sun.
New stem growth is green, and looks and feels like an herbacious stem. Mature stems are a brown or gray color that exfoliates in vertical strips. In cold climates the plant often dies back to the ground each winter, and so the more mature bark is often not present. The leaf is gray-green in color on the top (very pale green beneath) and lanceolate in shape with a finely serrated margin. The underside of the leaf is pubescent, as is the short petiole.
In summer, long (4-10 inches) panicles of colorful flowers bloom that emerge on new growth. They have a fragrant smell and are very attractive to butterflies and moths, which flock to the bush throughout the bloom season. It begins to bloom in mid summer and will bloom until the first frost.
Landscape Use
This plant shines in a shrub border where it adds some summer and fall interest with its bright and showy blossoms. I recommend planting it near a window or and outdoor living space where you can enjoy the butterflies that visit the bush. It is also a good choice for a particularly hot and dry location.
Points of Interest
Butterfly Bush may begin to spread and become invasive.
Notable Cultivars
Black Knight: One of the most cold hardy varieties. The blossoms are a very dark purple color.
Pink Delight: This cultivar has a smaller and more compact form - growing 5-8 feet high and wide. It is the most popular pink blooming variety.
Siberian Peashrub
Caragana arborescens
Plant Description
Caragana arborescens, or Siberian Peashrub, is a large shrub or small tree, reaching 15-20 feet tall and 12-18 feet wide. It is commonly found in a multi-stemmed form or grafted onto a standard as an small ornamental tree. It has a loose, upright branching habit. It is extremely cold hardy and tolerant of poor soils, pollution and drought. The bark is glossy and dark olive green, with prominent lenticels.
The leaf is evenly pinnately compound, 1 1/2 - 5 inches long and bright green to lime green in color. Each leaflet is elliptic in shape and can reach 1 inch long. Small thorns form at each node on the branch. On young growth the thorns are pliable and not particularly noticeable, but by the end of the season you will definitely notice them if you grasp the branch in your hand.
Yellow pea-like flowers appear in the spring and can be born individually or in small clusters. The flowers are moderately ornamental, but not showy. Flowers form on the previous year’s growth. Small (1 1/2 - 2 inches long) yellowish-green seed pods form on the bush during the summer and turn light brown in early fall.
Landscape Use
Use Caragana arborescens in difficult locations. It is a good choice for a windbreak or hedgerow.
Points of Interest
Dirr claims that you can hear the pea-pods pop when they burst in late summer, though I have never waited around a specimen long enough to verify this.
Notable Cultivars
Walker: The leaves of this cultivar are very slender and nearly needle-like in size and texture, creating a very light and airy feel to the plant. It also has a strong weeping form. This cultivar is most commonly grafted onto a standard and sold as a small ornamental tree.
Smokebush
Cotinus coggygria
Plant Description
Cotinus coggygria, or Smokebush, is a hardy and fast growing large shrub or small multi-stemmed tree growing 10-15 feet high and wide. It is tolerant of a wide range of soils and different pH levels, but performs best in full sun in a well-drained dry location. It has a spreading and open form that is typically wider than it is high. It can become scrubby looking if left unpruned.
The leaf is an attractive squat oval leaf, often times nearly round in shape, with an entire margin. They are 1 1/2 - 3 1/2 inches long and arranged alternately on the stem. The leaf is thin, and translucent in sunlight. The bark is a dark red-brown color with noticeable lenticels. The pith of the stem is orange in color. The leaf is green in the summer and turns a mixture of oranges and reds in the fall.
In the early summer, small yellow flowers appear which are not ornamentally important. Instead, it is the long and airy pedicles that create the show. The large clusters of pedicles create what looks like small clouds of smoke on around the canopy of the bush. When early morning dew is resting on the pedicles it creates the mirage of a thousand tiny sparkling diamonds suspended above the foliage.
Landscape Use
It is best used at the back of a shrub border to provide a nice color backdrop and where the illusion of the smoke will be most efficacious. It can be used as an ornamental tree, though it will require regular pruning to keep it looking food. Also a good choice for any hot and dry areas.
Points of Interest
Leafspot and powdery mildew can be a problem, especially when the foliage is regularly sprayed with water.
Notable Cultivars
Grace: The larger leaves are a translucent purple color when young and mature to a deep green. It has a gorgeous red and orange fall color.
Royal Purple: Perhaps the most common cultivar, it has nearly circular deep purple leaves. The pedicles are a bright red color.
Golden Spirit: A yellow-leaved cultivar that has circular leaves and beautiful bright yellow new foliage. The young foliage is often tinged with red or green around the margin. The smoke effect is not as good.
Rose of Sharon
Hibiscus syriacus
Plant Description
Hibiscus syriacus, or Rose of Sharon, is a large shrub or small tree, reaching 8-12 feet high and 6-10 feet wide. It is a hardy and tolerant plant, but does not cope well with extremes of soil or moisture. It forms an upright, oval shape with a fairly dense branching form. It performs best in a hot, full sun location - but be sure that it has adequate irrigation.
The leaf has three distinct lobes with an irregular serration on the margin of the leaf. They are a bright and vibrant green and slightly lustrous. The leaves are arranged alternately on the stem. In late summer and into fall, the shrub puts on a great blossom display, with individual flowers 2-4 inches across. The flowers have five-petals and can be white or any number of shades of purple, depending on the cultivar.
The fruit appears as a brown capsule. It is cone-shaped with a rounded base, and eventually bursts open to create a 5-pointed star shape. I think that the seed capsules are somewhat ornamental because of their unique and geometric shape.
Landscape Use
Because of its size it is best used in a shrub border or deeper perennial border.
Points of Interest
The flowers are very attractive to butterflies and hummingbirds.
Notable Cultivars
Ardens: This double bloom variety has purple-pink blossoms.
Lucy: The dark pink blossoms on this variety are nearly red in color. The flowers are double blooms.
Red Heart: Pure white single blossoms have a prominent red center.
Hydrangea
Hydrangea macrophylla
Plant Description
Hydrangea macrophylla is one of the most showy flowering shrubs during the summer months and is commonly found throughout moist climates with acidic soils. It grows 3-6 feet high and wide, but can grow larger in ideal conditions (which are not found in Utah), and has a strong round form. It rarely branches, but rather thick stems grow quickly from the ground to fill in the plant. It grows best in more temperate conditions and is borderline for our area.
The large (4-8 inches long) leaves are obovate or elliptic in shape with large serrations along the margin of the leaf with the tip of the leaf forming an elongated point. The veins are set into the leaf, making the venation very noticeable. Leaves can vary quite a bit in color from a bright green to a dark and lustrous green. The leaves are arranged oppositely and new leaves and new growth form at the terminal bud, causing the new leaves to emerge in tightly rolled between the existing leaves before they unfurl as they mature.
In the summer Hydrangea puts on a spectacular flower display. The large corymbs of small flowers are either rounded or flat-topped. They can be up to 10 inches wide and are found in copious amounts on the plant. Bloom color in many cultivars varies depending on the soil pH, with acidic soils creating blue and purple colored blossoms, while alkaline soils will create pink blossoms. The blossoms form on the previous year’s growth, so trim the shrub after flowering is completed.
Landscape Use
It is a great selection for a shrub border or perennial border, where its flower display will make it really pop in the landscape. In more temperate climates I have seen it often used as a loose hedge plant with great effect.
Points of Interest
Winter dieback is common in our climate, but can be minimized by siting the plant in a protected location. I recommend planting it in part-sun to full-shade, but have seen several good specimens (especially Annabelle) in full sun.
Hydrangea macrophylla needs plenty of water to prevent it from wilting. If a plant has become droopy, ample water will typically revive it quite quickly.
Notable Cultivars
Endless Summer: This may the best-known designer plant. The marketing campaign for Endless Summer has nearly turned it into a household name. It grows 3-5 feet high and wide and famously blooms continually throughout the summer and into fall.
Hydrangea paniculata ‘Pinky Winky’: The long-lasting flowers form in conical panicles (instead of the rounded or flat corymbs of Hydrangea macrophylla). They emerge white before turning a pink color in the end of summer. Hydrangea paniculata is hardier than Hydrangea macrophylla, performing well in zones 3-9.
Hydrangea paniculata ‘Limelight’: The cone-shaped panicles of flowers are a light limey green color. Hydrangea paniculata is hardier than Hydrangea macrophylla, performing well in zones 3-9.
Hydrangea arborescens ‘Annabelle’: Very large corymbs of white blossoms (up to a foot wide) bloom during the summer. It can be cut back nearly to the ground every winter.
Tulip Tree
Liriodendron tulipifera
Plant Description
Liriodendron tulipifera, or Tuliptree, is a large shade tree, reaching 70-90 feet tall and 35-50 feet wide. It has a tall and upright form with a limited number of thick and large branches that give the tree a very strong skeletal appearance during the winter. It prefers a moist and slightly acidic soil, but will tolerate a wide range of soil and moisture conditions except for drought.
The leaf is unique shaped, nearly perfectly mirrored down the central vein of the leaf. The leaf has three to four squat lobes with understated points at the end of each lobe. The way the topmost two lobes are formed on the leaf creates an indented shape on the end of the leaf. The leaf is a true green color and turns yellow in the fall.
Semi-ornamental, 2-3 inch long flowers appear on the ends of the branches of the tree in the spring. The flowers have a cup-shape, like that of a tulip, and are a yellow-green color. The flowers are quite attractive but unfortunately, face upwards, making them much less ornamental than they could be. Cone-shaped aggregate seeds form in the summer and turn brown in the late fall. The cone is actually a collection of individual samaras seeds which fall throughout the winter.
Landscape Use
It is best used in large sites such as campuses and parks. Plant next to a multiple storied building where the occupants of the building can appreciate the upward-facing blooms.
Points of Interest
Tuliptree is particularly susceptible to aphids and scale. Aphids can be particularly troublesome, causing the leaves of the tree to become very sticky and irregularly glossy in appearance.
Northern Lights Hybrid Azalea
Rhododendron x Northern Lights
Plant Description
Rhododendron x Northern Lights Hybrids, or Northern Lights Azalea is a small to medium (3-6 feet high and wide) flowering deciduous shrub with a distinct tropical feel. Although Azaleas are typically an evergreen plant grown in a temperate climate - these deciduous Azaleas are extremely cold hardy. They grow best in moist and acidic conditions, but will tolerate our soils and heat as long as they are adequately watered.
The leaves are oblong, arranged alternately on the stem. They are a bright green to dark green in color. The bright and showy flowers form in clusters at the terminal buds, with 4-10 flowers per cluster. The flowers emerge in the spring and come in a number of bright and showy colors, most notably pinks, yellows and oranges. The flowers have five petals with long stamens curling up at the ends. They have a very tropical feel.
Landscape Use
Use as a flowering plant in a shrub or perennial border. The tropical appearance of the blossoms make it a good selection for a plant next to a patio or window.
Points of Interest
Use as a flowering plant in a shrub or perennial border. The tropical appearance of the blossoms make it a good selection for a plant next to a patio or window.
Notable Cultivars
Golden Lights: Bright yellow blossoms and better disease resistance. Grows five feet high and wide.
White Lights: Pure white blossoms with a dusting of yellow color in the throat. Five feet high and wide.
Mandarin Lights: Bright orange blossoms. Grows 6 feet high and wide.
Rosy Lights: Deep and vibrant pink blossoms and the largest cultivar, growing up to 8 feet high and wide.
Weigela
Weigela florida
Plant Description
Weigela florida, commonly just referred to simply as Weigela, is an old-fashioned plant that has recently seen a surge of popularity thanks to an abundance of new cultivars. It is a medium to large sized shrub, growing 6-9 feet high and 9-12 feet wide, though the majority of cultivars are smaller than 5 feet. It has a dense, rounded to spreading form with long arching branches. The new growth can make it look somewhat wild in appearance. It grows best in a hot and sunny location with dry, well-drained soil.
The stem is a pale brown color with large lenticels. The leaves are elliptic to ovate in shape with a finely serrated margin. The leaf comes to a point at the tip and is rounded at the base. The actual species is a rich green color, but most of the popular cultivars are either purple-leaved or variegated.
The real charm of Weigela is its period of profuse blooming in the spring. The tubular flowers are bright pink, 1-2 inches long, and form all along the length of the stem. They can form singly or in a small clusters. The flowers bloom for 5-6 weeks, with the most showy period lasting approximately 20 days. Flowers will continue to appear sporadically throughout the summer and into fall, but nowhere near the numbers as in spring. During the summer, elongated seed capsules form on the plant. They are not ornamentally important.
Landscape Use
Use in shrub or perennial borders or as a foundation planting. It is a good choice for dry and difficult sites where it should thrive with only minimal supplemental irrigation. I have not seen it used in parking islands but don’ t see why it would not perform well in that location.
Points of Interest
It is a hardy and vigorous grower, but can suffer from substantial winter die back. Prune out any dead wood to encourage new growth and keep a good form.
Notable Cultivars
Midnight Wine: A dwarf selection with very dark purple foliage and bright pink flowers. It grows on 18-24 inches high and wide.
Alexandra (Wine & Roses): One of the most popular varieties. It has purple foliage and hot pink blossoms. It grows 4-5 feet high and wide.
My Monet: A variegated dwarf variety of Weigela. The leaves are green with a variegated white margin tinged with light pink hues. The flowers are pink. It grows 18-24 inches high and wide.
Red Prince: A larger green-leaved variety. The flowers are a bright red and stand out against the foliage. Grows 5-6 feet high and wide.
Minuet: The leaves are green with a purple overcast. The flowers are a dark pink or red.
Japanese Wisteria
Wisteria floribunda
Plant Description
Wisteria floribunda, or Wisteria Vine, is a large and vigorous climbing vine capable of growing up to 40 feet long. It will twine itself clockwise around structures in order to climb and can be heavy enough that a structure needs to be sturdy enough or risk collapse. The main stems of Wisteria can grow to be several inches in diameter and with a supporting structure it can be trained to grow in to a tree. It is very hardy and can deal with any number of soil and moisture conditions, though it can take it a couple years to get fully established.
The leaf is alternate pinnately compound and bright green in color. The leaf grows about a foot long and can have up to 19 leaflets on each leaf. Each leaflet is ovate in shape with smooth margins. When the leaves first emerge they are very pubescent.
During late spring or early summer, large hanging racemes of purple blossoms appear. On a mature fine the blossoms will cover a vine and are extremely showy and fragrant. Few thing compare to sitting under an arbor with a Wisteria vine in full-bloom overhead. Wisteria typically does not flower until the vine is 4 or 5 years old. Four inch pea pods form on the plant in the summer and turn brown by fall. They persist into the winter.
Landscape Use
Use as a climbing vine on structures or supported along walls. It is most commonly used on arbors, pergolas or pavilions where people are able to enjoy both visual and olfactory impact of the blossoms.
Points of Interest
In more temperate climates Wisteria can quickly get out of hand if not regularly pruned. Young plants can suffer from leaf scorch if not given plenty of water.
