Archive for the ‘Trees and Shrubs’ category

Mahonia Aquifolium (Oregon Grape Holly)

September 19th, 2008

A Tough, Ornamental Evergreen

Mahonia aquifolium is a glossy evergreen shrub native to the Pacific Northwest. It features pinnate leaves on long, irregular stems. The individual leaves are leathery, spiny, and resemble holly. The shrub is somewhat coarse in habit, but is still an interesting and ornamental addition to a cold hardy tropical garden. It will eventually reach 8 feet in height, and will spread out via suckers to reach 3-5 feet in diameter.

It is known as the Oregon Grape Holly due to the bluish-black berries it forms from late summer through autumn, which resemble grapes.

Mahonia aquifolium is hardy to Zone 5, and tolerates a wide range of growing conditions. It prefers rich organic soil but is very adaptable. It can grow in full sun to full shade, in well-drained soil or clay, and tolerates seasonal flooding.

Nandina Domestica (Heavenly Bamboo)

May 9th, 2008

A bamboo-like shrub with striking foliage

About Nandina Domestica

Nandina domestica, or heavenly bamboo, is completely unrelated to bamboo. Its name comes from its fine, bamboo-like foliage and its cane-like stems. It is an evergreen to deciduous shrub that will grow to 5 feet tall , 3 feet wide, at a moderate rate. Some sources list Nandina domestica as hardy only to zone 7, but it is hardy to zone 6 with some dieback. It will lose its leaves at 10°F, and at -10°F, its stems will die back to the ground. Recovery is quick in the spring.

Nandina domestica (heavenly bamboo) \'Monum\'
Nandina domestica ‘Monum’ / Plum Passion® (Heavenly bamboo). The colorful, finely-textured foliage creates a striking contrast with big-leaved background plants like Musella lasiocarpa.

Many named cultivars of heavenly bamboo exist, each with different variations in color. Many nandinas feature tropical-looking leaf color combinations of brilliant reds, bronzes, and greens, as well as bright red color in the fall. Some cultivars recently offered by Monrovia have notably superior foliage color. They include ‘Monum’ (Plum Passion®), ‘Monfar’ (Sienna Sunrise™), and ‘Firepower’.

Nandina domestica may be grown in partial shade, but the foliage colors will be much more intense if it is grown in sun. It prefers a moist, somewhat rich, acidic soil. Once established, it becomes very adaptable and will tolerate a wide range of conditions. Site the plant to protect it from harsh winds.

Cold Hardy Camellias

May 5th, 2008

About Camelias

Camellias are evergreen shrubs or small trees with attractive glossy foliage. They originate from subtropical regions of China, Japan and neighboring countries. They are known for their dramatic blooms during the off-season – autumn, winter, or early spring, depending on the cultivar and climate.

Typically, camellias have been grown only in the southern United States, but more recently, the development of cold-hardy cultivars has extended their potential growing range considerably.

Hardiness

Several camellia cultivars have been developed that are hardy to zone 6. A select few, such as those developed by Dr. William Ackerman at the National Arboretum, are hardy to -15°F, and may be worth trying in zone 5.

Camellia \'Snow Flurry\'
Camellia ‘Snow Flurry’

The Hardiest Camellias

  • Camellia japonica
    A spring-blooming camellia. Cultivars hardy to zone 6b: “April Series” (‘April Dawn’, ‘April Kiss’, ‘April Blush’, etc.), ‘Betty Sette’, ‘Frost Queen’, ‘Jerry Hill’, ‘Pink Icicle’, ‘Red Aurora’, ‘Red Jade’, ‘Spring’s Promise’, ‘Bernice Boddie’.
  • Camellia oleifera
    Tea-oil camellia, hardy to zone 6. Often used to hybridize with camellias with showier flowers.
  • Camellia oleifera Hybrids
    Ackerman Hybrids
    Developed by Dr. William Ackerman at the U.S. National Arboretum in Washington, D.C. Hardy to zone 6, some selections possibly to zone 5. Named cultivars: ‘Ashton’s Pride’, ‘Frost Prince’, ‘Lushan Snow’, ‘Pink Icicle’, ‘Polar Ice’, ‘Snow Flurry’, “Winter Series” (‘Winter’s Beauty’, ‘Winter’s Charm’, ‘Winter’s Dream’, etc.).
  • Camellia Forest Hybrids
    Developed by Camellia Forest, hardy to zone 6. Named cultivars: ‘Mason Farm’, ‘Survivor’, ‘Twilight Glow’.
  • Camellia sinensis var. sinensis
    A small-leaf tea camellia, hardy to zone 6. Originally grown from seeds collected in Korea where it was growing in the wild; it had probably escaped from cultivation. This variety is vigorous and grows as a shrub, 6 to 8 ft. tall.

Winter Protection

Site camellias to protect from cold, drying winds. Make sure the plant is heavily mulched around the base; small plants can be completely covered with a loose, non-compacting mulch. Application of an antidessicant spray such as Wilt-Pruf® will reduce moisture loss during the winter.

Growing Tips

Camellias prefer light shade when young. Growing in well-drained, organic soils is essential. Camellias prefer slightly acidic soil, but do not amend the soil to be too acidic or overfertilized.

Tropical-Looking Shrubs and Other Plants

December 6th, 2007

These tropical-looking plants don’t quite fit into the other categories – small, tropical-looking deciduous shrubs, hardy citrus, eucalyptus, and yuccas. They work well with evergreen trees and shrubs, and deciduous trees to create a permanent framework for your tropical garden.

Dediduous Shrubs, Yuccas, and More:

  • Buddleia davidii (Butterfly bush) : Zone 5-10
  • Hibiscus syriacus (Rose-of-sharon) : Zone 5-9
  • Hydrangea macrophylla (Bigleaf hydrangea) : Zone 6-10
  • Spirea x bumalda ‘Goldflame’ (Goldflame spirea) : Zone 4-8
  • Eucalyptus Neglecta (Omeo Gum) : Zone 7-10
  • Poncirus trifoliata (Hardy orange) : Zone 5-9
  • Yucca ‘Bright edge’ (Bright edge yucca) : Zone 4-10

Yucca ‘Bright Edge’

Yucca ‘Bright Edge’

from Variegated Foliage Nursery

Tropical-Looking Deciduous Trees

November 29th, 2007

Tropical-looking deciduous trees are valuable because they are typically large and easy to grow, creating a framework around which other tropical-looking plants can be arranged. The tropical effect may come from large, exotic-looking leaves; palm-like, finely-divided leaves; or some other feature, such as interesting flowers, fruit, bark, or branch structure.

Deciduous Trees

  • Albizia julibrissin (Silk tree / Mimosa tree) : Zone 6-9
  • Aralia elata (Japanese angelica tree) : Zone 3-8
  • Asimina triloba (Pawpaw) : Zone 5-9
  • Catalpa bignonioides (Southern catalpa / Indian bean tree) : Zone 5-9
  • Cladrastis lutea (Yellowood) : Zone 4-8
  • Franklinia alatamaha (Franklin tree) : Zone 6-9
  • Gleditsia triacanthos (Honey locust) : Zone 4-9
  • Juglans nigra (Black walnut) : Zone 4-9
  • Kalopanax pictus (Castor aralia) : Zone 4-8
  • Laburnum x watereri ‘Vossii’ (Golden chain tree / Golden rain tree) : Zone 6-8
  • Lagerstroemia indica (Crape myrtle) : Zone 6-10
  • Liriodendron tulipifera (Tulip tree / Tulip poplar / Yellow poplar) : Zone 5-9
  • Magnolia macrophylla (Bigleaf magnolia) : Zone 5-9
  • Paulownia tomentosa (Royal paulownia / Empress tree) : Zone 5-9
  • Quercus fusiformis (Escarpment live oak / Scrub live oak) : Zone 6-10
  • Robinia pseudoacacia (Black locust) : Zone 4-9

Common Laburnum

Common Laburnum

Tropical-Looking Broadleaf Evergreen Trees and Shrubs

November 2nd, 2007

Many varieties of trees and shrubs are valuable in a tropicalesque garden for their tropical-looking foliage, flowers, or general habit. Some trees and shrubs are fully hardy, yet add a tropical aura to a landscape. Certain trees and shrubs that have been traditionally grown in warmer areas, such as the southern United States, are hardier than commonly thought, and are worth trying in a colder climate to achieve a tropical look.

Some of these plants may be valuable for their glossy foliage; others for their large, jungle-like leaves. Others may have finely-divided palm-like leaves, tropical-looking flowers, a unique bark texture, or an interesting trunking habit.

Tropical-looking broadleaf evergreens are notable for glossy evergreen foliage that can extend the garden’s tropical look past the prime season of many deciduous plants.

Broadleaf Evergreen Trees and Shrubs

  • Camellia (Camellias)
  • Gardenia augusta ‘Grif’s Select’ (‘Grif’s Select’ gardenia) : Zone 6-10
  • Magnolia grandiflora (Southern magnolia)
  • Mahonia aquifolium (Oregon grape / Holly-leaved barberry) : Zone 5-9
  • Nandina domestica (Heavenly bamboo) : Zone 6-11
  • Pieris japonica (Japanese pieris) : Zone 5-8
  • Rhododendron (Rhododendrons)
  • Rhododendron (Azaleas)

Magnolia Grandiflora Edith Bogue

Magnolia grandiflora ‘Edith Bogue’