Return to: MREC Home Page
CFREC-A Foliage Plant Research Note RH-91-5
R.W. Henley, L.S. Osborne and A.R. Chase
Central Florida Research and Education Center - Apopka
2807 Binion Road., Apopka, FL 32703-8504
Reference to University of Florida/IFAS Pest Control Guides
The aralia family (Araliaceae) is composed of 84 genera of herbs and woody plants ranging from vines to trees (2), including the genus, Polyscias. Within Polyscias, there are approximately 80 species of trees and shrubs indigenous to Polynesia and tropical Asia, most of which are commonly called aralias. Many aralias are useful interior plants and landscape plants in tropical areas of the world. Leaves of Polyscias are arranged alternately on the stem and are usually compound. Several cultivars have attractive variegated foliage.
Although there are several plants outside Polyscias which have aralia as part of their common name, this publication will be limited to aralias within Polyscias. Nomenclature of Polyscias has not been well defined until recently. The L. H. Bailey Hortorum staff (2) listed 4 species and 9 cultivars and Graf (6) listed 5 species and 8 cultivars. More recently, Burch and Broschat (3) studied the aralias grown in south Florida and described 8 species and 21 cultivars. Commercial producers of interior foliage plants in Florida listed for sale 6 species and 7 cultivars in 1985 (1) and this has fluctuated slightly since that time. It is estimated that one can find 25 or more species and cultivars of polyscias in Florida nurseries, the landscapes of southern Florida and in private collections.
Several of the most popular polyscias are described below:
Polyscias balfouriana (Refer to P. pinnata)
Polyscias crispa `Chicken Gizzard' (Chicken Gizzard Aralia)
The chicken gizzard aralia is also known as celeryleaf aralia. This upright plant branches rather freely and bears leaves which are pinnately divided with usually more than 3 rounded leaflets that have 2 or more lobes.
Polyscias crispa `Palapala' (Palapala Aralia)
Palapala aralia is similar in branching habit and leaf characteristics except the leaflets are attractively patterned with dark green, golden yellow and ivory. Propagators should know that `Palapala' is patented (plant patent number 3775).
Polyscias filicifolia (Fernleaf Aralia)
The fernleaf aralia is a distinctly upright shrub which branches freely. It bears pinnately divided leaves which resemble the fronds of some ferns.
Polyscias fruticosa (Ming Aralia)
Ming aralia is one of the most popular of the polyscias with its upright-spreading growth habit and fine-textured, pinnately-divided leaves. Because of the wide crotch angle of the branches and the openness of the fine foliage, the trunk and many of the attractive branches are exposed, lending additional beauty to the plant.
Polyscias fruticosa `Elegans' (Parsley Aralia)
The parsley aralia is an excellent dwarf cultivar with leaves that resemble some of the finely-divided strains of parsley. It produces an abundance of side shoots and compactly-arranged, small leaves that make it a good choice for small pots in the 4 to 8-inch diameter range.
Polyscias guilfoylei `Blackie' (Black Aralia)
Black aralia is a strongly upright, sparsely branched plant with very dark green, pinnately-divided leaves. The leaflets have a unique, but not especially decorative, wrinkled surface texture.
Polyscias pinnata `Dinnerplate' (Dinnerplate Aralia)
The dinnerplate aralia is predominantly upright and open. The pinnately-divided leaves usually have 3 or more large, rounded leaflets which accounts for the cultivar name.
Polyscias pinnata `Marginata' (Variegated Evergreen Aralia)
The cultivar `Marginata' is similar in growth habit to `Dinnerplate' except the leaflets are smaller, usually more numerous, and have an irregular white margin. This plant is occasionally listed as P. pinnata `Tricochleata'.
Polyscias pinnata `Pennockii' (Pennock Aralia)
The leaf size and shape of the Pennock aralia is like the cultivar `Marginata', but the leaflets have an attractive blend of ivory, yellow and dark green patches.
Polyscias tend to be produced predominantly in south Florida due to their slow growth rate and their application in landscaping. The products grown in south Florida nurseries tend to be in the 6 to 14-inch pot, diameter range. In recent years there has been increased interest among central Florida nurserymen to produce polyscias in 4 to 8-inch diameter pots. The plants are excellent interior plants, well adapted to light levels of 125 foot-candles or higher. The upright forms are used as specimen shrubs by commercial interiorscapers. Some of the dwarf cultivars with an upright- spreading branching habit, such as P. fruticosa `Elegans', are good choices for 4 to 8- inch pots. The ming aralia and its dwarf cultivars are excellent candidates for bonsai.
Polyscias can be propagated from softwood terminal cuttings under intermittent mist or hardwood cuttings (cane) without foliage. Cuttings should be stuck in a well drained nursery mix with high water-holding capacity. Rooting hormones will enhance the rooting process. Direct-sticking technique is preferred because plant roots should be disturbed as little as possible during propagation. Heavy misting during propagation is discouraged because best rooting occurs in a medium which is not waterlogged.
Some growers propagate polyscias successfully under polyethylene film tents erected over greenhouse benches. This technique provides elevated daytime temperatures, increases the humidity and minimizes the amount of water applied during rooting. If possible, provide a root zone temperature range of 70-75°F during propagation.
Calcium and magnesium are normally applied by blending dolomite at the rate of 4 to 10 pounds per cubic yard of potting medium to adjust the pH to approximately 6.0. The amount of dolomite used will depend upon the initial acidity of the medium. A fertilizer with a 3-1-2 to 2-1-2 ratio should be used at the rate of 2.5 to 3.0 pounds of actual nitrogen per 1000 square feet per month once the propagules have rooted. Light level range for good nursery growth and dark green leaf color is 1500 to 4500 foot-candles. Plants grow best at temperatures of 70 to 85°F.
1) Rapid loss of older leaves
2) Slow growth and slow loss of lower (older) leaves
3) Pronounced "birdnest" type growth and stunting of tip growth
Reference Pest Control Guides Here
1) Xanthomonas leaf spot (Xanthomonas campestris pv. hederae)
Reference Pest Control Guides Here
1) Anthracnose (Colletotrichum gloeosporioides)
Symptoms - Lesions are initially water-soaked and surrounded by a yellow halo. Eventually, they can reach 1 inch in diameter and turn tan to black in color. The tiny black fruiting bodies of the pathogen are readily detected in the lesions on the upper leaf surface. Most lesions occur on leaf margins or in wounded areas.
Control - Elimination of overhead watering and exposure to rainfall can reduce disease incidence and severity.
2) Alternaria leaf spot (Alternaria panax)
3) Pythium root rot (Pythium spp.)
4) Rhizoctonia aerial blight (Rhizoctonia solani)
Reference Pest Control Guides Here
INSECT AND RELATED PROBLEMS
The major arthropod pests of this plant species include fungus gnats, mealybugs, mites, and scales. Mealybug, mite, and scale infestations are typically the result of bringing infested plant material into the greenhouse. In the control section for each pest, a few of the many registered and effective pesticides will be listed. The list by Short et al. (1984) should be used only as a guide to the sensitivity of foliage plants to pesticides. Another publication by Short et al. (1989) provides a summary of insect and mite management information for foliage plants.
1) Fungus gnats
Symptoms - Fungus gnats are small black flies (1/8 inch long) and are frequently observed running around the soil surface or on leaves and are often confused for Shore flies (see later section). The adults have long bead-like antennae and their legs hang down as they fly. These insects are very weak fliers and appear to "flit" around randomly. The larvae are small legless "worms" with black heads and clear bodies that inhabit the soil. The larvae spin webs on the soil surface which resemble spider webs. Damage is caused by larvae feeding on roots, root hairs, leaves in contact with the soil and lower stem tissues. Feeding damage may predispose plants to disease and they are often found in close association with diseased plants or cuttings. Adults do not cause any direct damage, but are responsible for many consumer complaints to growers. Adults emerge and fly around in retail shops, homes, or offices and are therefore a nuisance. For further information please consult Extension Entomology Report #74 (Management of fungus gnats in greenhouse ornamentals).
3) Mites (Broad mite)
4) Mites (Twospotted spider mite)
Phytotoxicity data for this plant are limited. If a pesticide is required, small group of plants should be tested for phytotoxicity prior to treating the entire crop (See Chase et al. 1981).
Pesticides should be applied according to label
Regardless of the pesticide or mixture of
pesticides used, it is
strongly recommended that the effects be evaluated on a few
plants, under your particular conditions before treating all plants.
Mention of a commercial or proprietary product
in this paper
does not constitute a recommendation by the authors,
nor does it imply registration under FIFRA as amended.
Reference Pest Control Guides Here
1. Anonymous. 1985. Florida Foliage Locator 1985-1986. Florida Foliage Association, Apopka, FL. 188 pp.
2. Bailey, L.H. Hortorum staff. 1976. Hortus Third. MacMillan Publishing Company, Inc., New York, NY. 1290 pp.
3. Burch, D.G. and T.K. Broschat. 1983. Aralias in Florida horticulture. Proc. Fla. State Hort. Soc. 96:161-164.
4. Chase, A.R. 1990. Phytotoxicity of bactericides and fungicides on some ornamentals. Nursery Digest 24(5):11.
5. Chase, A.R., T.J. Armstrong and L.S. Osborne. 1981. Why should you test pesticides on your plants? ARC-Apopka Research Report RH-81-6.
6. Graf, A.B. 1978. Tropica. Roehrs Company-Publishers, East Rutherford, NJ. 1120 pp.
7. Price, J., D.E. Short and L.S. Osborne. 1989. Management of fungus gnats in greenhouse ornamentals. Extension Entomology Report #74.
8. Short, D.E., L.S. Osborne and R.W. Henley. 1984. Phytotoxicity of insecticides and miticides to foliage and woody ornamental plants. Extension Entomology Report #57.
9. Short, D.E., L.S. Osborne and R.W. Henley. 1991. 1991-1992 Insect and related arthropod management guide for commercial foliage plants in Florida. Extension Entomology Report #52. 13 pp.
10. Simone, G.W. and A.R. Chase. 1989. Disease control pesticides for foliage production (Revision #4). Plant Protection Pointer. Extension Plant Pathology Report #30. [also in Foliage Digest 12(9)1-8]