Spring blossom dreams - flowering trees for Rocky Mountain States - Brief Article

Sunset, Dec, 1999 by Dick Bushnell

To make them come true, choose mountain-hardy flowering trees this winter

Now that falling leaves have given way to snowflakes, a mountain gardener's thoughts naturally turn to spring and fresh planting possibilities. Soon the New Year's mail will bring a new crop of plant catalogs filled with tempting color photographs, including those of deciduous spring-flowering trees. But trees that bloom beautifully on paper may be miserable candidates for mountain gardens, where high elevations, subzero cold, and late frosts exert tremendous stress on plants.

Which flowering trees are best for the mountain West? We asked growers and nursery staffs from Colorado to Idaho to name some of their handsome, hardy favorites. Their suggestions, reflected in the list here, include many trees that add year-round beauty to the landscape, displaying not only showy spring blossoms but also handsome summer foliage, often ornamental or edible fruit, colorful leaves in autumn, and interesting bare forms in winter. Except as noted, these trees are recommended for Sunset climate zones 1-3. Keep in mind, though, there's no guarantee that a late frost won't nip the buds or blossoms of early bloomers.

The trees listed are sold variously as bare-root, balled-and-burlapped, or container stock. Order bare-root plants soon for delivery in spring or shop for them at nurseries. If you can't find the trees you want locally, ask your nursery to order from a regional wholesale grower. Set out plants as soon as your garden soil is workable. Locate fruiting trees such as crabapple and serviceberry away from patios or paving.

Tough trees with pretty spring blooms

* Crabapple

Malus hybrids bear pink, red, or white blossoms, followed by showy fruit in red or yellow, and autumn leaves in shades of red, orange, or yellow. These named varieties offer a range of flower colors: 'Adams' (pink), 'Brandywine' (fragrant rosy pink doubles), 'Centurion' (rosy red), 'David' (white), 'Indian Magic' (deep pink), 'Indian Summer' (rosy red), 'Prairifire' (pinkish red), 'Profusion' (purplish pink), 'Robinson' (deep pink), 'Spring Snow' (fragrant white blooms; little or no fruit), and 'Thunderchild' (deep pink to rosy red). These varieties range from 12 to 25 feet tall and 12 to 20 feet across. Plant them in full sun. All these are hardy to 6,000 feet, some much higher.

* Dogwood

Cornelian cherry (Cornus mas) carries small yellow flowers on bare twigs in early spring, followed by clusters of bright scarlet fruit (good for making jelly or attracting birds). Reaches 20 feet tall, 15 feet wide. Takes sun to filtered shade. Hardy to 6,500 feet.

Pagoda dogwood (Cornus alternifoIia) displays creamy white flowers in spring, followed by blue-black berries and red and yellow autumn leaves. Reaches 20 feet tall, 20 feet wide. Filtered shade. Hardy to 6,000 feet.

* Hawthorn

In the landscape, hawthorns work well as stand-alone accents or as hedges or screens.

Cockspur thorn (Crataegus crus-galli) bears white flowers, red fruit, and leaves that turn orange to bronzy red in autumn. Thorny branches form a striking winter silhouette. Reaches 20 to 30 feet tall with an equal spread. Thornless C. c-g. 'Inermis' grows to 25 feet tall, 20 feet wide. Sun. Hardy to 8,000 feet.

Colorado hawthorn (Crataegus succulenta) bears white flowers in late spring, then red fruit and red-to-purple autumn leaves. Reaches 25 feet tall, 15 feet wide. Sun. Hardy to 9,000 feet.

Russian hawthorn (Crataegus ambigua) is covered by white flowers in spring, small red fruit in summer, and leaves that turn yellow, orange, and red in fall. Reaches 25 feet tall, 20 feet across. Sun. Hardy to 9,500 feet.

* Lilac

Japanese tree lilac (Syringa reticulata) bears long, showy clusters of faintly scented white blossoms in late spring. Reaches 30 feet tall, 20 feet across. Sun. Hardy to 6,500 feet.

* Magnolia

These deciduous magnolias can be grown at elevations below 6,000 feet in warmer parts of zones 2 and 3 (Boise, Denver, and Salt Lake City). They will need protection from cold winds and winter sun, plus filtered shade in hot-summer areas.

Saucer magnolia (M. soulangiana) bears saucerlike blossoms to 6 inches across in shades of white to lavender-pink. Reaches 25 feet tall with an equal or wider spread. Hardy to 6,000 feet.

Star magnolia (M. stellata and M.s. 'Rubra') shows off stunning white or rosy pink blossoms with star-shaped petals in early spring. Grows 10 feet tall, 20 feet wide. Hardy to 6,000 feet.

* Ornamental pear

Pyrus fauriei 'Korean Sun', a new fruitless variety, has white flowers and red-to-purple autumn leaves. Reaches 12 to 20 feet tall, 15 feet wide. Sun. Hardy to -25 [degrees].

* Prunus

Chokecherry (Prunus virginiana 'Canada Red', also sold as 'Shubert') bears clusters of tiny white flowers, followed by tart, dark red fruit, and reddish purple autumn leaves. Reaches 25 feet tall, 25 feet wide. Sun. Hardy to 9,000 feet.

Flowering plum (Prunus nigra 'Princess Kay'), a new introduction by Colorado's Plant Select program, bears double white flowers in spring, red autumn leaves. Reaches 20 feet tall, 15 feet wide. Sun to partial shade. Hardy to 7,000 feet.