7 Spectacular & Underused Small Flowering Trees
I think small flowering trees are the bread and butter of a well-balanced landscape. They impart aesthetic value that other plants can’t fully render by providing unique structure, form and color display. They provide practical value such as easing wind and heat pressures, especially when planted in groups or with larger shade trees. Flowering trees also supply ecological value, providing nectar and pollen for bees, and leaves for caterpillars that become butterflies and moths. Having plants that flower in spring (when most trees bloom) is imperative in this regard since pollen and nectar are less abundant than summer and fall.
The flowering trees you’re likely familiar with are popular for good reason. Flowering dogwood (Cornus florida), Eastern redbud (Cercis canadensis), flowering crabapple (Malus spp.), and flowering cherry (Prunus spp.) are all beautiful trees. That said, there are other flowering trees that are just as spectacular but for one reason or another, don’t share the limelight. Seven of them, which I’ll list here, are excellent choices for most landscapes in terms of beauty and durability – and they’re all worthy of your consideration.
#1 Flowering Hawthorn (Crataegus spp.)
Like crabapples and cherries, there are many types of hawthorns. A cultivar of green hawthorn (Crataegus viridis) called “Winter King” is my personal favorite. Winter King hosts prolific white flowers in mid-spring after most crabapples and cherries have finished. In autumn, excellent fall color and brilliant red berries (technically called haws) provide dramatic appeal. These pea-sized fruit are persistent into mid-winter, covering the bare branches in a kingly red haze (hence the moniker). After a couple freeze-thaw cycles, the fruit becomes palatable to overwintering birds.
Winter King is, like many hawthorn types, tolerant of dry soils and difficult sites, making it a very reliable choice. I periodically see this tree used successfully in street and parking lot “hell strips.” Its tolerance of miserable areas, however, doesn’t mean its aesthetics are compromised. Three employees, myself included, have made space for this tree in our gardens because we love it.
Another great hawthorn is the Proven Winners introduction “Crusader” which is a cultivar of Cockspur hawthorn (C. crus-galli). This tree is similar to Winter King but lacks thorns, a plus for those with small children. The fruit is a little larger than Winter King, however, and not persistent through winter.
Both species are native and provide great benefits to birds and pollinators, as are many other hawthorns.
Most landscape hawthorns, such as the ones noted above mature at 20-25’ high and wide, which is about the same as other small ornamental trees.
Note: Avoid planting hawthorns near junipers (Juniperus spp.) to reduce the risk of the cedar-hawthorn rust, an unsightly but non-fatal fungal pathogen that blemishes the leaves.
#2 American Fringe Tree (Chionanthus virginicus)
The most unique flowers of any tree, in my view, belong to the American Fringe tree. The wispy white flowers are not individually grandiose but when one stands back, the tree appears encircled in billowy white clouds. Like hawthorns, fringe trees usually flower after landscape staples such as crabapple, redbud, and cherry have finished.
Fringe trees are dioecious which means trees are usually separate sexes (like hollies). Male flowers on male trees are marginally showier while females produce small blue-black fruits later in the season. The fruit is not messy, but birds will make short work of them anyway.
While typically an understory tree in the wild, this natural multi-stemmed tree becomes fuller when planted in sunny locations. The golden fall color is respectable and tends to be more pronounced on specimens planted in full sun.
While tolerant of difficult soils and exposed sites, the American fringe tree performs best with middle-of-the-road conditions in terms of soil texture and moisture. Mature size is small, averaging 15-20’ high and wide. I must emphasize the “natural” habit of this tree when young, so it may be preferable in less formal settings.
#3 Carolina Silverbell (Halesia carolina)
“A sensational native that is too frequently absent from American landscapes…Every landscape would be well served by a silverbell.” – Horticulturists Michael Dirr & Keith Warren
These sentiments apply here in the Pittsburgh region, given the excellent aesthetic value and reliability of the Carolina Silverbell. Prolific white bell-shaped flowers open in spring and have dramatic effect when the trees are tall enough for you to stand under and gaze upward.
Fall color is yellow, and like the American Fringe tree, is more pronounced on specimens in sunnier locations. When young, the multi-colored, fissured bark is modestly attractive.
Although not fussy, the Carolina Silverbell appreciates the same specific growing conditions that flowering dogwoods do, namely well-drained soils rich in organic matter and moisture. Similarly, part sun is recommended as this is an understory tree, but full sun will work fine if the site isn’t too hot, dry, or exposed.
While the species hosts white flowers, we also carry pink flowering forms including “Arnold’s Pink” and “Rosy Ridge” (faster growth rate). Mature size is comparable to dogwoods and redbuds, 20-30’ high and wide.
#4 Sourwood (Oxydendrum arboretum)
While most trees in our region flower in spring, sourwoods bloom in summer. Like the American Fringe tree, Sourwoods have a very “natural” growth habit when small but will mature into a fine structured specimen – so have patience! The fragrant, white bell-shaped flowers are reminiscent of Pieris japonica and are abuzz with pollinators as soon as they open. The cream color of the seed capsules further gives the appearance the tree is flowering longer than it actually does. Fall color of this species is difficult to rival, reliably having vivid red, purple, and maroon tones.
Sourwoods don’t demand “maintenance” but they will not tolerate subpar growing conditions. Site in well-drained soils rich in organic matter and even moisture. I recommend planting in a partly sunny location with some wind protection such as along a wood edge. For those with a miserable spot in mind, forget it, but otherwise I’m always delighted to recommend one.
In cultivation, sourwoods mature at 20-30’ high, with half to 2/3 the width, but note this tree is a slow grower.
#5 Japanese Stewartia (Stewartia pseudocamilia)
The Japanese Stewartia is a prime example of a plant with four season interest. Attractive thick, green leaves emerge in spring followed by camellia-like flowers in summer; this is neat since camellias are not hardy in our region. Fall tones are heavy with reds and purples. The exfoliating bark reveals multiple colors and textures with age, which stands out in winter when not overpowered by foliage or flowers.
The cultural needs mirror other woodland ornamental trees. Soils rich in organic matter that are moist but well-drained are a must. Full sun and part sun are both acceptable but keep away from overly hot and exposed areas such as along streets and on windy hilltops.
Mature size varies based on the region. Many horticultural texts say a mature specimen ranges between 20-40’ high. In northern, noncoastal areas with shorter growing seasons like ours, 20-30’ is a mature specimen. Width will be about 2/3 the height.
#6 Blackhaw Viburnum (Viburnum prunifolium)
Though sometimes classified as a large shrub, I consider Blackhaw viburnum more utilizable in the landscape as a small tree. Like the popular serviceberry (Amelanchier spp.), this flowering tree grows naturally in multi-stem form but can be trained to grow as a single trunk specimen.
Large clusters (cymes) of white flowers appear in late spring and are, in my view, quite dramatic. Flowers are followed by small edible black fruit in summer which birds enjoy. Fall color is reliably vivid, heavy in tones of reds and purples. Though most trees on this list are fantastic for wildlife, Blackhaw viburnum might lead the pack in terms of ecological productivity. Mature size is around 15-20’ high and wide.
Viburnums are well known for being adaptable and this species is no exception. Blackhaw will grow in full to part sun and in average-moist to dry soil. Like Hawthorns, this species can tolerate periods of drought once established.
A similar species called Nannyberry (Viburnum lentago) is also available from time to time. It’s similar in most respects but is less resistant to powdery mildew. It’s still a splendid tree, however, and should be planted in a spot with good air flow.
#7 Witch-hazel (Hamamelis spp.)
“I like witch-hazels because they brighten up a garden when almost nothing else is in bloom. Their wide, spreading branches carry strap-like flowers that are unique and very interesting to me.” – Aaron Grabiak
Like Blackhaw viburnum, witch-hazels straddle the line between large shrub and small tree. Unless you’re going to resist any hedging urges you might have when growing them as large shrubs, I recommend utilizing them as small, multi-stemmed trees.
Most witch-hazels you’ll find in nurseries originate from 4 species. They all grow similar in size and habit and have very distinguishable flowers. That said, there are differences that make them all special!
Hybrid witch-hazel (H. x intermedia)
is a cross between the Chinese (H. mollis) and Japanese (H. japonica) species. The most popular form is “Arnold’s Promise” which flowers early (February/March), has a stately vase-shaped habit, and boasts nice orange-yellow fall color. Flowers are bright yellow with red centers. The cultivar “Pallida” has larger, soft-yellow flowers. “Diane” has smaller red flowers, orange-red to red fall color, and a wider growth habit. “Jelena” has larger copper-red flowers, a vase-shaped habit, and orange to orange-red fall color. All flower around the same time (late winter) and average between 15-20’ high and wide. While tolerant of heavy shade, full to part sun is best.
Vernal witch-hazel (H. vernalis)
is native to the Ozark region of the US. Average height is around 10’ with a somewhat greater spread. Habit is denser with lower branching and suckering, so this species can function equally as a background shrub or a small specimen tree. Vernal witch-hazels also flower in late winter and with noticeable fragrance too. Leaves emerge reddish before turning green. Fall color is a respectable yellow. While quite tolerant of alkalinity, soggy soils, and heavy shade, full to part sun in moist, well-drained soil is best.
Common witch-hazel (H. virginiana)
is native to most of the eastern US and matures around 15-20’ high and wide in the landscape. While similar in appearance to other witch-hazels, the fragrant flowers on this species open in mid-fall, usually late October/early November. I consider this species to be a fantastic choice as it extends the flowering season later in the garden than any other plant. Fall color is a reliable, rich yellow. Common witch-hazel is very adaptable and will grow in full sun to full shade (with a more attractive habit in full sun) as long as soils aren’t permanently wet or dry. While witch-hazels may appear dainty, they are quite tough – especially this one. The cultivar “Harvest Moon” has larger flowers which appear even later when most of the foliage has dropped.
We Need More Diversity in Our Landscapes
There are more flowering trees of course, but the list above is an excellent place to start beyond the ever-popular dogwood, redbud, crabapple, and cherry. Don’t get me wrong, they’re fantastic trees – but they aren’t the only fantastic trees out there. If you’re a homeowner looking to add a flowering ornamental or two to your landscape this year, I encourage you to use this list as well as our Plant Finder tool here (View All Trees 1 to 10 of 360 – Plumline Nursery Plant Finder – Pittsburgh Murrysville Plum Monroeville Trafford Pennsylvania PA).
My advice also applies to landscapers who use our plants in their work. Be sure to avoid using the same plants too often, and in the same ways, so designs don’t become monotonous or stagnant. There are many wonderful trees available and far too many are neglected simply because they’re less familiar. Talk to us and we’ll help you add more trees to your design palette.
At Plumline Nursery, our model isn’t to sell cheap, common, mediocre-quality plants as fast as possible. Our goal is to offer a superior selection of high-quality plants and to give you the customer service you need to make your gardens and landscapes successful. Keep that in mind and we hope to see you soon!