Tuesday, November 27, 2012

Nandina Domestica, Evergreen Shrub of The Day



Nandina domestica
    Heavenly Bamboo

Type    Shrub, woody plant
Hardy range    6B to 9B
Height    6' to 10' / 1.80m to 3.00m
Spread    12" to 36" / 30cm to 90cm
Growth rate    Average
Form    Upright or erect
Exposure    Partial shade or partial sun to full sun
Persistence    Evergreen

Bloom Color    White
Bloom Time    Spring

The flowers are showy.

Environment
This plant tolerates some drought and some salt.
This plant will grow in dry soil.
Suitable soil is well-drained/loamy, sandy or clay.
The pH preference is an acidic to alkaline (less than 6.8 to more than 7.7) soil.

Leaf Color    Green and purple
Fall Color    Red
This plant has attractive foliage and attractive fall colors.

Culture Notes
With bamboo-like stalks and delicate, fern-like foliage, Nandina is much-prized for its oriental effect and distinctive appearance.  Adding to its appeal are large, erect panicles of creamy white flowers in spring followed by decorative bright red berries in fall and winter.  Berries are eaten by a variety of birds and this can spread the plant to neighbors yards.  Nandina spreads slowly by underground stems, providing attractive clumps for entryways, containers, or as specimen plantings in a ground cover.  They also add an accent to the front of a shrub border when planted in groups or clumps.  Plant on 2 to 3 foot centers for a mass planting, farther for a more open effect.

Nandina in partial shade will exhibit richer-colored red fall foliage than if planted in the sun.  Foliage diseases will be less in full sun.  Although tolerant of drought once established, rich soil and ample moisture will produce a lusher, better-looking plant.  Plants survive with neglect, although regular fertilization encourages growth and thicker plants.  Plants have been reported as invasive into selected natural areas in Florida and other southern states.

Nandina is a low maintenance shrub, requiring only one pruning each year to control plant height, if needed.  The tallest canes should be trimmed to the ground or to different heights in early spring to reduce the size.  This will provide for more foliage toward the ground and promote a denser plant.  Recent selections have produced several dwarf cultivars, and although most of these do not flower and fruit, they do produce vividly-colored fall foliage and can be used as a ground cover. Some are nicer than others.

Dwarf cultivars available include:  `Atropurpurea Nana' is a rather ugly, reddish plant; `Compacta', purplish winter color, 4 feet tall; `Firepower', red to maroon fall foliage, 2 feet tall, virus free which gives it superior foliage; `Gulfstream', reddish-bronze fall foliage, 4 feet tall, upright habit, suckers from the base; `Harbor Dwarf', bronze fall foliage, 1.5 to 2 feet tall; `Moonbay' and `Nana Purpurea', both are rounded and spread, and they have red fall foliage and are 1.5 to 2.5 feet tall; and `Woods Dwarf', red to maroon fall foliage, 1.5 feet tall.  The dwarf cultivar `Lowboy' flowers and produces red berries, reaches 3 feet in height, and has red fall foliage. This plant is considered mostly allergy free and causes little or no allergy problems in most people.

Planting and establishing shrubs
The most common cause of young plant failure is planting too deep.  Plant the root ball no deeper than it was in the nursery.  In most instances, the root flare zone (point where the top-most root in the root ball originates from the trunk) should be located just above the landscape soil surface. Sometimes plants come from the nursery with soil over the root flare. If there is soil over this area, scrape it off.  The planting hole should be at least twice the width of the root ball, preferably wider.  In all but exceptional circumstances where the soil is very poor, there is no need to incorporate anything into the backfill soil except the loosened soil that came out of the planting hole.  Never place ANY soil over the root ball. If a row or grouping of plants is to be installed, excavating or loosening the soil in the entire bed and incorporating organic matter enhances root growth and establishment rate.

Weed suppression during establishment is essential.  Apply a 3-inch thick layer of mulch around the plant to help control weed growth.  Keep it at least 10 inches from the trunk.  If you apply it over the root ball, apply only a one or two inch layer.   This allows rainwater and air to easily enter the root ball and keeps the trunk dry.  Placing mulch against the trunk or applying too thick a layer above the root ball can kill the plant by oxygen starvation, death of bark, stem and root diseases, prevention of hardening off for winter, vole and other rodent damage to the trunk, keeping soil too wet, or repelling water.  Regular irrigation through the first growing season after planting encourages rapid root growth, which is essential for quick plant establishment.