Our new ‘Top Trees’ series highlights Martin’s favourite trees under 10 metres for use in urban home landscapes. This month, we showcase trees that flower in spring and beyond!
All noted trees are 10 metres or less in height at maturity, designated for Zone 5 (or under), and are native to, or naturalized within, Ontario.
Medium (10m high x10m wide)
'Leonard Messel' Magnolia (Magnolia X loebneri)
The Magnolias draw crowds in the spring when its beautiful two-toned flowers usher in the season. You can often smell its fragrant blossom before you see it! Leaves turn a vibrant yellow, orange or red during the fall.
Compact, hardy, low-maintenance cultivar with multi-stemmed habit & beautiful two-toned flowers + showy fruit
Blooms in early spring; fragrant flowers feature strap-like petals - white inside, purplish-pink outside
Cone-like fruit ripens to red in late summer
Excellent architectural specimen in urban landscapes, courtyard gardens or shrub borders
Magnolia × loebneri, commonly called Loebner magnolia, is a deciduous hybrid magnolia (M. kobus x M. stellata). It is a small tree typically growing to 20-30’ tall with a rounded crown. It is more often grown in a multi-trunked form that as a single trunk tree. Fragrant star-like white flowers (4-6” wide) with 10-15 petals appear in early spring before the foliage. Flowers give way to cone-like fruits that ripen to red in late summer, releasing individual red coated seeds suspended on slender threads at maturity. Fruits are sometimes absent on this hybrid. Obovate, medium green leaves (to 5” long).
'Leonard Messel' is a cross of M. kobus and M. stellata 'Rosea'. Its flowers are less susceptible than most magnolias to late frosts.
Image credits: 1-3. Monrovia
Zone, Growing Conditions & Requirements
Zones 5 to 9. Best grown in moist, organically rich, well-drained loams in full sun to part shade. Medium water and maintenance needs. Generally intolerant of soil extremes (dry or wet). Intolerant of most urban pollutants. May take 3-4 years before first blooms appear. Time to ultimate height: 20-50 years.
Problems: Magnolia flower buds are susceptible to late-season frosts; shelter large-leaved species from windy locations. No serious disease or pest problems.
Highlights & Design Tips
Flowering tree – fragrant with showy flowers and fruit. Excellent specimen tree for the lawn or shrub border, architectural city & courtyard gardens, cottage & informal garden patio, container plant. Effective on the periphery of a woodland area.
Noteworthy Characteristics:
Genus name honors Pierre Magnol, French botanist (1638-1715)
Specific epithet honors Max Loebner, a German horticulturist, who made the first cross of this hybrid in the early 1900s
Sources + more info:
Small (8m high x8m wide)
White Flowering Dogwood (Cornus floridia)
The flowering dogwood is an amazing native tree displaying both flowers and fruit. Flowers appear in the spring and can be red, white or pink. They bear fruit to which small birds are particularly attracted. Thrives in partial shade so best planted amongst large trees. They are able to adapt well to dappled light and absorb the sunlight wherever they can find it.
Amongst the most beautiful of native flowering trees
Showy flowers, fruit + fall leaf colour = multi-season interest
Low-branched tree has layered, horizontally spreading lines + low-topped crown
Bright red fruit is a food source for birds; matures in late summer; lingers late into the year
Flowers are comprised of tiny yellow-green clusters, surrounded by white petal-like bracts, & appear as a single large white flower
Cornus florida (flowering dogwood) is a small deciduous tree that typically grows 15-30’ tall with a low-branching, broadly-pyramidal but somewhat flat-topped habit. It arguably may be the most beautiful of the native American flowering trees. It blooms in early spring, shortly after (but usually overlapping) the bloom period of the redbuds.
The true dogwood flowers are actually tiny, yellowish green and insignificant, being compacted into button-like clusters. However, each flower cluster is surrounded by four showy, white, petal-like bracts which open flat, giving the appearance of a single, large, 3-4” diameter, 4-petaled, white flower. Oval, dark green leaves (3-6” long) turn attractive shades of red in fall. Bright red fruits are bitter and inedible to humans (some authors say poisonous) but are loved by birds. Fruits mature in late summer to early fall and may persist until late in the year.
Image credits: 1-3. Missouri Botanical Garden
Zone, Growing Conditions & Requirements
Zones 5 to 9. Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Prefers moist, organically rich, acidic soils in part shade. Benefits from a 2-4” mulch which will help keep roots cool and moist in summer. Medium maintenance. May be inadvisable at this time to plant this tree in areas where dogwood anthracnose infestations are present.
Tolerates: Deer, clay soil, black walnut
Problems: Flowering dogwood, when stressed, is susceptible to a rather large number of disease problems, the most serious of which is dogwood anthracnose. Plants are also susceptible to powdery mildew, leaf spot, canker, root rot and leaf and twig blight. Stressed trees also become vulnerable to borers. Leaf miner and scale are less serious potential insect pests.
Highlights & Design Tips
Flowering tree - popular as a specimen or small grouping on residential property around homes, near patios or in lawns. Also effective in woodland, bird or native plant gardens. Features multi-season interest: showy flowers, showy fruit, and good fall leaf colour. Attracts birds and butterflies.
Noteworthy Characteristics:
Genus name comes from the Latin word cornu meaning horn in probable reference to the strength and density of the wood. Cornus is also the Latin name for cornelian cherry
Specific epithet comes from the Latin word flos flower in reference to its attractive spring flowers
Common name of dogwood is a likely reference to an old-time use of hard slender stems from this tree for making skewers once known as dags or dogs
Sources + more info:
Small (10m high x 5m wide)
Japanese Tree Lilac (Syringia reticulata) A compact, sturdy tree that has showy, fragrant blooms, is resistant to most pests and diseases, transplants well and grows in a wide range of soil conditions.
Very tough tree with scented upright groupings of white flowers giving summer show. The bark is of interest during the winter season: brown contrasted with naturally-peeling grey.
A highly preferred tree over its frequently planted relative ‘Ivory Silk’, which does not have this bark feature but is often selected because of its smaller size, thus compromising valuable shade needed to enjoy our city gardens.
Mid-size tree-form lilac has upright growing habit, dense branching & makes for a lovely specimen in the landscape
Gorgeous panicles of creamy white flowers bloom in early summer
Showy display of green fruit ripens to a brown, dehiscent persistent capsule
Graceful form, showy dry seed pods, & brown bark studded with light-coloured lenticels pop against a winter landscape
Attracts hummingbirds & butterflies
Image credits: 1. Missouri Botanical Garden; 2. Landscape Ontario; 3. Missouri Botanical Garden
Zone, Growing Conditions & Requirements
Zones 3 to 7. The Japanese Tree Lilac is a mid-size deciduous tree-form lilac belonging to the olive family (Oleaceae). It has a moderate growth rate, upright growing habit, and a rounded to oval shape. Requires full sun and grows in a wide range of soil conditions. Medium water, low maintenance.
Problems: Superior resistance to powdery mildew disease
Tolerates: Deer, clay soil
Noteworthy Characteristics:
Very different from the plant most people associate with "lilac"
Flower scent is not particularly favoured by gardeners; while common lilacs have one of the plant world's most fragrant blooms, the tree lilac’s scent is often compared to the rather unsavoury stench of privet shrub (Ligustrum)
Highlights & Design Tips
A lovely flowering specimen in the landscape. Tree forms are effective along streets and in lawns; shrub forms are effective in borders or small groups. May be used as a screen along property lines.
It is small enough to grow near a deck or patio, and it lacks an aggressive root system that is hazardous around patios, walkways, driveways and septic lines.
Flowers later than common lilac and other flowering plants, displaying colourful blooms in early summer rather than late spring – useful when planning a flowering sequence in your garden.
Sources + more info:
1. The Spruce
Large (12m high x 10m wide)
Yellowwood (Cladrastis kentukea)
Previously known as Cladrastis lutea
Yellowwood is a native tree with an open graceful spreading crown and three seasons of interest. The hanging panicles of flowers in the spring become hanging yellow-brown fruits and leaf colour becomes yellow-orange in the fall. The smooth grey bark adds winter interest.
The root system is deep which makes transplanting difficult but allows shade-loving plants to grow underneath it. Shows well in a garden as a specimen feature as it likes sunlight - but when shrubs are planted around its base, it gives a spring and autumn effect. Yellowwood makes a great shade tree.
Fragrant & showy native tree provides 3 seasons of interest
Hanging panicles of white flowers in spring turn into hanging yellow-brown fruit in fall as leaves turn a yellow-orange colour; smooth grey bark adds winter interest
An open, graceful, spreading crown makes it a fantastic shade tree
Lovely when used in native, pollinator, or winter gardens, meadows or woodlands
Attracts bees, pollinators & songbirds + wildlife food source
Image credits: 1. Tom Gill, Plants CES NCSU; 2. Missouri Botanical Garden; 3. Connon Nurseries
Zone, Growing Conditions & Requirements
Yellowwood is medium-sized, deciduous tree of the Fabaceae (legume) family. Full sun, medium water, low-maintenance. Features upright branching and a broad, rounded crown. It is noted for its pinnately compound foliage, panicles of fragrant white spring flowers, autumn seed pods and yellow fall colour.
Pinnately compound leaves (7-11 leaflets) open as yellowish green, turn bright green in summer and then turn yellow in fall. Intensely fragrant, wisteria-like, pink flowers in large, drooping, terminal panicles (10-15” long) will cover a mature tree in late spring. Profuse bloom may occur only once every 2 or 3 years however. New trees may not bloom for the first 8-10 years. Bloom is similar in appearance to that of black locust (Robinia). Flowers give way to flat seed pods (2.5-4” long) that mature in September-October. Species was formerly called Cladrastus lutea.
Problems: No serious insect or disease problems. Verticillium wilt may occur. Trees will bleed if pruned at the wrong time. Bark is susceptible to sun scald. Bloom may be damaged by late spring frosts. Yearly bloom may not occur. Branching is fragile and vulnerable to damage from winter snow/ice or high winds.
Resistance to challenges: Diseases, drought, dry soil, insect pests, urban conditions
Noteworthy Characteristics:
Genus name comes from the Greek klados meaning branch and thraustos meaning fragile for the brittle twigs
Specific epithet means of Kentucky
The wood of this tree contains a yellow dye that distinctively colours the heartwood and gives rise to the common name of yellowwood
Highlights & Design Tips
Excellent small shade tree for residential lawns, particularly on smaller properties. May be planted near patios and terraces. May be effectively grouped on larger properties. Roots go deep, so other plants may be easily grown underneath its canopy.
Suggested landscape locations: Meadow, naturalized area, recreational play area, woodland
Suggested landscape themes: Children's garden, native garden, pollinator garden, winter garden
Sources + more info:
Comments