Description
These are evergreen perennial
herbs with stems growing erect or decumbent and creeping. Stems that grow along
the ground may root at the nodes. There is generally a crown of wide leaf
blades which in wild species are often variegated with silver and green coloration. The inflorescence bears unisexual flowers in a spadix, with a short zone of female flowers near the
base and a wider zone of male flowers nearer the tip. The fruit is a fleshy berry that ripens red. The fruit is a thin
layer covering one large seed.
Plants of the genus are native to humid, shady tropical forest habitat.
Cultivation and uses
Aglaonema
costatum
Aglaonema have
been grown as luck-bringing ornamental plants in Asia
for centuries. They were
introduced to the West in
1885, when they were first brought to the Royal Botanic
Gardens, Kew. They
have been cultivated, hybridized, and bred into a wide array of cultivars. They live in low-light
conditions and are popular houseplants.
This mainly tropical genus is known for its
intolerance of cold temperatures. Chilling injury can begin at 59°F. The injury manifests in dark,
greasy-looking patches on the foliage.
Cultivars have been selected for their shape and size,
and especially for the color and pattern of the leaves. Many have white or
cream-colored stems. Some have also been developed to tolerate colder
temperatures. The most common
cultivar is 'Silver Queen', which has gained the Royal
Horticultural Society's Award of Garden
Merit.
Most propagation of Aglaonema is done with cuttings and by dividing
the basal shoots. Care of the houseplant involves protecting it from cold
temperatures and excessive sunlight and removing any inflorescences that
develop, which can prolong the life of the plant. It requires moist soil, and
while some cultivars require a small amount of fertilizer, plants are easily injured when
oversupplemented. Aglaonema are prone to false mites (Brevipalpus
californicus. They may also acquire populations ofnematodes, such as root-knot nematodes and Pratylenchus species, which cause root lesions. Pathogens include
the fungusMyrothecium roridum and bacteria such
as Pseudomonas
cichorii, Erwinia
chrysanthemi, and Xanthomonas
campestris, which can all cause leaf spot. Colletotrichum fungi can cause anthracnose.
Aglaonema plants
are poisonous due to calcium oxalate crystals. If ingested they cause
irritation of the mucous membranes, and the juice can cause skin irritation and
painful rash.
