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Tantalizing Tropical Marginals

by Craig Presnell, Florida USA
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 Water Rose Cactus


Pereskia bleo
Water rose cactus (Pereskia bleo) is a primitive member of the family Cactaceae and the least succulent of the cacti. Native to Panama and Colombia, this beautiful shrub reaches a height of 1-2 m (3-6 feet), and grows along river banks and in association with emersed Echinodorus. The stems do have spines typical of the family, but what is not typical are the large, flat non-succulent leaves. The blooming period is said to be from summer to fall and numerous rose shaped flowers colored a bright red-orange are produced. Protected in a shadehouse, the bloom has continued well into the winter. The flowers produce odd shaped, non-edible fruits that are bright yellow.
Water rose cactus starts easily from cuttings that can be placed immediately in damp soil without a drying period. A tropical plant, it is hardy to USDA zone 9b, but the leaves are deciduous at temperatures below 5 C (40 F). In summer, it thrives in constantly moist soil, humid air and light sun to bright shade. Winter care includes protection in zones colder than 9b and drier conditions. 



Fire Fingers 
Fire fingers (Sanchezia nobilis) is a tropical in the family Acanthaceae from the lowlands of northern South America. It is an evergreen, herbaceous shrub that ranges in height from 1.5-2 m (4-6 ft). Known primarily for its vivid foliage of light green leaves with yellow-white veins, in early summer it does produce an inflorescence of yellow bracts with red flowers. In addition to its bold tropical appearance, the flowers attract both butterflies and hummingbirds.


Sanchezia nobilis
Listed as hardy to USDA zone 9a, it will drop its leaves at temperature of 5 C (40 F) or less. A heat lover, it does best at temperatures above 20 C (60 F) and requires constantly moist but not saturated soil. It prefers partial shade, but also does well in areas that receive morning sun. In winter, water can be reduced and, in areas colder than 9a, it can be treated as a house plant. 



Water Banana 

 
Typhonodorum
lindleyanum

The water banana (Typhonodorum lindleyanum) is named for its resemblance to a banana plant, but is actually a large aquatic aroid. Endemic to Madagascar and neighboring islands, this impressive aroid can attain heights of 3.5 m (12 feet). A tropical perennial, it will tolerate temperatures to 20 C (60 F) but prefers temperatures in excess of 25 C (77 F) and high humidity. The bloom is a spadix characteristic of members of the Arum family; with a prominent white spathe, the bloom is reminiscent of Peltandra sp. flowers.

Unquestionably, Typhonodorum is best used as a specimen plant in the tropical water garden. It grows well in full sun and its roots in still waters. Leaves as large as 150 cm (5 feet) on a long banana-like pseudostem are the reason for the common name of water banana, but the sagittate leaves more closely resemble the leaves of Alocasia or Peltandra. The seeds produced are as large as 3 cm (1+”) and edible.

In as much as it is hardy only to USDA zones 10-11, winter protection is a must. The plants to some degree will grow to fit their containers, so potted plants can be moved to a heated greenhouse when the whether cools. The larger the pot, the larger the plant, the more greenhouse space required, but it is a specimen plant that to me loses some of its appeal if dwarfed too severely. The alternative for hobbyists that can provide the plant with an early start is to save seed. At temperatures above 25 C, the seed sprouts readily in saturated soil. Given warm temps, full sun and ample fertilizer, the sprouts grow quickly and really ... if you can overwinter a banana (Musa), you can most likely overwinter Typhonodorum. For a little more effort you could then have a water banana, rather than a banana in water. 



Pandan 

Pandan (Pandanus amaryllifolius), a tropical plant in the screwpine family, is a staple in southeast Asian cooking. Also known as “Bai Toey”, “Rampe” and “La Dua”, the fresh or wilted leaves are added as a flavoring agent and can also be used as a green food dye.

The plant itself grows to be an herbaceous shrub up to 2 m (6 feet) in height. Long, narrow, blade-like green leaves grow directly from the trunk in fan-shaped sprays. As the plant matures woody aerial prop roots are formed. Several interesting observations lead researchers to think that Pandan has a long history of cultivation and may actually be a cultigen or anthropogenic plant … that is to say, it is not a naturally occurring plant, but is derived from artificial selection and/or alteration by man. The facts that suggest this are: pandan is the only member of the screwpine family with aromatic leaves; it rarely flowers and then only sterile male flowers are produced; and it is not known to occur in the wild.


Pandanus amaryllifolius

A perennial, the pandan plant is hardy to USDA zone 9, but is frost tender and so must be protected or the leaves will be lost. It grows best in shade to filtered sun and requires constant moisture and regular feeding with a general use fertilizer. We use a 14-14-14 top dressing and supplement it with 20-20-20 soluble diluted to half strength. It is resistant to pests and in some areas the dried leaves are used as a cockroach repellent.

Given its low maintenance, edibility and tropical look, the pandan is an interesting addition to any water garden. 


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