BOTANIC GARDENS LIBRARY SL~GAPORE The history of the National Parks Board will certainly 25 MAR 1997 Botanic Gardens spans nearly a thrive. Achievement of its mission to century and a half, and has been well make "our nation our garden" will be documented in the books facilitated by the loosening of "Singapore Green" and "Visions constraints that hampered the of Delight" by former staff Bonnie former government department. Tinsley. We now need new editions to these books, as the Gardens In the re-constituted National enters a new chapter in its history. Parks Board, the Singapore Botanic Gardens will retain its divisional In 1973, the Singapore Botanic status under the new Director, Dr. Gardens merged with the Parks and Chin See Chung. Its role and status Trees Branch of the Public Works will be underlined as the flagship of Department to form the Parks and the nation's fl eet of parks and ~ sage Recreation Division of that gardens. The Gardens will serve as department. The title of Director of the nerve centre for advancing the the Singapore Botanic Gardens was recreation, research, conservation from re-designated as "Deputy and education programmes of the Commissioner of the Parks and Board when the new headquarters of the Recreation Division". In 1976, the the National Parks Board move to Parks and Recreation Division was the Gateway core of the Gardens. accorded departmental status. By Increasingly, the Singapore Botanic CEO ... the early 1980 s, many of the Gardens will play a key part in functions of the Gardens had been defining the role and identity of new given over to different branches in generation botanic gardens. Its the Parks and Recreation unique value as an equatorial botanic Department, and the Gardens was and horticultural institution cannot reduced in status to that of a branch be understated at a time when global in the Research and Development biodiversity is under siege. The Division. directions and management C 0 N T E N T S initiatives developed at the Gardens Message from the CEO 2 The parent ministry of the can have a significant impact in the Parks and Recreation Department, region and beyond. These are From the Director 3 the Ministry for National exciting times for the The Role of Singapore Botanic Development, formed the National Botanic Garden:;; . · Gardens in a City Economy 4 Parks Board in 1990. The functions ''.""~r-·•:1'<~ of the Research and Development Mrican Yam 5 Division of the Parks and Recreation Pollination Mechanisms of Department were subsumed under Orchids 6 this Board, along with the administration and development of The Aroid House 8 the nature reserves and Fort Bromeliads 10 Canning Park. The original role and Annuals in Your Garden 14 functions of the Singapore Botanic Gardens were restored under the Jewels of the Water 15 Executive Director of the Board. Front Cover illustration: Mr Maulud bin Elin Holding In the six years since its A 16 KgDioscorea Tuber formation, the National Parks Board forged a strong identity with its fresh initiatives and management programmes. The Singapore Botanic Gardens drafted a new Masterplan to take it into the 21st century as a N~PARKS leading institution for tropical botany and horticulture. Implementation is Editors: Chin See Chung now under full steam. In July 1996, Foong Thai Wu the parent ministry decided to merge the Parks and Recreation Designer: Department with the National Parks Eng Siak Loy Board, with the former Executive Production Manager: Director at the helm as the Chief WongWeiHar Executive Officer. Given the synergy of the merger, the increase in critical NATIONAL PARKS BOARD Singapore Botanic Gardens mass, resources and expanded Cluny Road, Singapore 259569 portfolio, the newly re-constituted

2 We proudly present this flrst education. We will contribute issue of Gardenwise of the post towards ex-situ conservation to the merger period. It represents a From extent that our limited land tangible expression of the resources will permit, and we will commitment and effort of the the propagate and make available in Gardens' staff as they rally and large numbers, selected rare and adjust to the organisational changes. endangered species to relieve the Director... pressure on the wild. The Singapore Botanic areas for rest where food and Gardens enters its 138th year with beverages are served and an internal In formal horticultural the confidence, courage and transport system, it is anticipated education we aim to be a regional creativity to meet the new challenges that visits will also lengthen. centre offering quality teaching and ahead as Singapore's premier park Needless to say the quality of our training to meet increasing demands and as an institution of international horticultural displays and landscapes for practitioners in this fi eld. To help standing. must match that of the facilities fulfil our roles and responsibilities in planned. nurturing interests in recreational Today's botanic institutions horticulture, developing nature must not only be repositories of To lay flrm claim as a leading awareness and appreciation, our botanic collections and sanctuaries tropical botanic garden we will need activities in public education will be for botanic and horticultural to recapture the role of the expanded. research, but they must also be Singapore Botanic Gardens as a resources for recreation and centre of excellence for botanical Gardenwise is a supporting education. The Singapore Botanic and horticultural research and vehicle for education. It is also an Gardens, in particular, must embody publication. Tropical horticulture outlet for our staff to communicate these multiple roles because land is and botany, in particular the their horticultural and botanical such a scarce resource. The , breeding and micro experiences in the less esoteric Masterplan that has been drawn up propagation of orchids are our themes to our friends here and for the Garden's development fully priority. To create a garden of overseas, and it will track major addresses these needs. Major greater botanical interest and value, happenings in the gardens. developments are being efforts to increase our diversity implemented to create a critical mass will be intensifled. As a responsible This 'new' Gardenwise, now of attrac~ion~ that will make the modern institution in an era when the Newsletter of the Singapore u"'r""'n" a mo.r~ important human impact on tne environment Botanic Gardens, will be published ' . ,... ~<>t.~~~:~l aJ1d:a majoJ·:Jo ~c~\iim~: ~t?:r >'#'~t f.~:««- ., a.l}d July. The With its strong emphasis on recreational retreat and acts as a breeding and cultivating commercial "green lung" only minutes away from tropical orchids, Singapore aims to the busy tourist belt downtown. A remain a key player in the world's stroll through the tranquil, shaded orchid trade. Today, the Singapore lawns and lush tropical plantings of Botanic Gardens' role in promoting the Gardens offers respite from the the country as a major source of city's hustle and bustle. orchids is to focus on developing new orchid hybrids, especially those with While the Gardens continues cut-flower potential, for the industry. to make its contribution to the country's economy, it also includes conservation as a major component Role Of Singapore Botanic Gardens of its mission. The Nature Conservation Unit co-ordinates all In A City Economy conservation programmes and the Another present day role of National Parks Board is the scientific the Gardens in relation to the authority on conservation matters in country's economy is in the Singapore. Singapore, with a total land promotion of Singapore's tourism 2 area of 641 km , is home to a trade. The Gardens received 2.4 The Gardens also contains a population of 3 million people, million visitors in 1995. Foreign small but precious remnant of the targeted to reach 4 million beyond visitors made up 66% or 1.58 million rain fo rests of the region. The the year 2000. With limited land and of the total. This represented Singapore Botanic Gardens' four­ natural resources, trade and tourism approximately 24% of Singapore's hectare rain forest is one of a few are key factors contributing to a total international tomist traffic, an remaining patches of primary forest robust economy. indication of the Gardens' popularity in Singapore. It offers tremendous as an attraction to our visitors. potential as a tangible, educational The Singapore Botanic resource for students and Gardens has a long history of Among the new attractions in researchers. contribution to the country's the Gardens is the National Orchid economy starting from its role in the Garden which was opened in October Although the findings of a development of the rubber industry. 1995. This is one of the most 1990 survey show that the forest has In 1877 seedlings of the Brazilian comprehensive permanent done surprisingly well after 130 years Para Rubber Tree, reputedly exposition of orchid culture in . of isolation, it does appear that smuggled to Kew Botanic Gardens, The three-hectare display draws on remedial action is now necessary to were sent to Singapore. A the Singapore Botanic Gardens' maintain the primary forest subsequent Director of the Gardens, longstanding, pioneering tradition of character and its biodiversity. A Henry Ridley, successfully orchid breeding in creating a major problem is the invasion of propagated more from the seeds of memorable recreational and exotic species. We have in place a these first trees and later, devised a educational experience for visitors. programme of selective weeding and method of tapping the white latex reforestation involving public from matured trees. This eventually Another attraction, soon to be outreach and community support to led to the start of a massive growth completed in 1997, will further try to address these issues. industry in the Malayan region. enhance the Gardens' value as a top tourist attraction. This is the S$12.8 In the next phase of the Over the years the Gardens million Singapore Botanic Gardens Gardens' redevelopment masterplan, has taken on a key role in the GatewayNisitor Centre complex. the National Parks Board is development of the commercially Comparable to a "village" centre, the augmenting the critical mass of important cut-flower orchid trade in Gardens Gateway will be bounded by attractions in the Gardens to improve Singapore. The country exports a rainforest on one side and an its value as a key tourist destination about S$20 million worth of fresh arboretum on the other. With its as Singapore strives to achieve a orchids a year, making it one of the ample car and coach parking tourism target of 10 million arrivals top orchid exporters in the region. facilities and visitor amenities such and $16 billion in total spending by as an Interpretative Area, cafeteria the year 2000 under the National Singapore's major and souvenir shop, the Gateway is Tourism 21 plan. breakthrough in commercial orchid poised to assume its role as the new growing was in 1929. Mr R E Main Entrance to the Singapore One of the proposed facilities Holtum, then Director of the Botanic Gardens. will be a cloud forest conservatory. Gardens, successfully germinated This will be the first attempt in the and grew man-made hyb rid seedlings While Singapore takes pride in tropics to create on a large scale a in sterile media. His works being an economically suc:..:essful conservatory with requirements encouraged an active breeding nation, the Government is also contrary to those found in European programme, which laid the concerned with the quality of life in and American gardens. The aim is to foundation fo r Singapore to become Singapore. In this respect, the recreate environmental conditions of a leader in commercial orchid Singapore Botanic Gardens plays a montane forests of the equatorial grovving and export of cut flowers. very important role as a social and region. This cloud fo rest facility will

4 Visitors to the patch of rain The toxicity of these bulbils and the forest in the Singapore Botanic tubers ensures their high survival Gardens frequently come across a AFRICAN rate. H. M. Burkill (The Useful vigorous climber, twining itself of West Tropical Africa, 1985, tightly to other plants. The volume 1) mentioned that the bulbils distinctive, almost heart-shaped leaf YAM are also adapted for water dispersal. with nine main veins radiating from (DIOSCOREA the base and waxy-white fleshy stem The tuber of D. sansibarensis that twines to the left, distinguish SANSIBARENSIS) can grow to a massive 30 kg. The this plant readily from others. This largest tuber excavated recently climber, Dioscorea sansibarensis or from the forest floor of the Gardens African Yam from Tropical West and weighed 16 kg. Exposed tubers are Central Africa has firmly established able to sprout at several places due itself in Singapore. to their stored food supply. Though the wild form of this species is toxic The species was introduced and is known to contain alkaloids, into the Gardens before 1928. A the tubers are considered as famine sample collected in the Gardens and or emergency food. Mr Maulud bin made into a herbarium specimen by Elin, a gardener with the Singapore a former Director, Prof. R.E. Botanic Gardens for 37 years, stated Holttum, is dated 1928. According to that the toxic tuber can be eaten him (Plan t Life in Malaya, 2nd ed., after careful processing by cutting 1973), this plant was introduced into into smaller pieces and washing in the Singapore Botanic Gardens for water before boiling. Sometimes, experimental purposes. these cut tubers are detoxified by leaving in running water for a few Another former Director, Mr days. Other species of Dioscorea I.H. Burkill, who studied the genus have long been cultivated in Africa, Dioscorea in great detail wrote in Asia and the New World for their the Annual Report of the Director of edible tubers. Examples are D. alata, Gardens, Straits Settlements (1915), D. batatas and D. trifida. that African yams were received through the Royal Botanic Gardens, While it looks like Dioscorea Kew from the Gold Coast and from sansibarensis will remain in the southern Nigeria. D. sansibarensis Gardens for quite some time, efforts is one of the species of African Yams are now underway to save some of that could have been introduced into 2 our native forest species from being the Gardens during that time. 1. Diosco1·ea sansibarensis showing its distinctive smothered by it. This is particularly leaves. true for those plants growing at the 2. Uprooted tubers awaiting disposal sprouting The proliferation of this plant readily. forest fringe. The Gardens' ground in open, cleared areas such as forest staff, including Mr Maulud, are fringes is due to its high degree of even as the leaves and stem shrivel. constantly on the look-out for plants resilience and amazing ability to By concentrating its food reserve of this species. Tubers are being dug propagate vegetatively. Though it into bulbils, the plant is able to out and disposed of to prevent them does not produce seeds in Singapore, regenerate itself after it has been from regenerating new plants and is it regularly propagates itself rapidly cut. The bulbils sprout rapidly into one aspect of forest management in through the production of purplish new plants once shed from the the Gardens to maintain the integrity brown bulbils from the leaf axils shrivelled stem after about three of this patch of natural forest. along the stem. After a leafy stem weeks. Underground tubers will be has been cut, bulbils would continue formed and will increase in size year TayEngPin to develop from buds at the leaf-axils by year once the plant is established. Curator/Horticulture make possible the maintenance and activities, such as public education biodiversity and natural areas. The study of a distinctive group of plants courses, guided tours and Gardens aims to strike a balance with tremendous potential for publications as vehicles to promote between both roles through strategic horticultural application. As tropical understanding and appreciation fo r planning, backed up by an cloud forests are increasingly our natural heritage, and for enthusiastic staff and close liaison subjected to land clearing activities, imparting the urgency for the with private and public the successful development of this protection and conservation of organisations. facility in the Gardens will provide an biological diversity. important learning resource. The Singapore Botanic Wong WeiHar The School of Horticulture, as Gardens is an important resource fo r Assistant Director/Singapore Botanic Gardens part of the Singapore Botanic the country's economy as well as an Management Gardens, in addition to formal organisation dedicated to the courses also utilises outreach conservation of Singapore's

5 Pollination is a process Besides providing food for the example, the bee-pollinated whereby pollen is transfered from pollinators, the calli masses may Dendrobium crumenatum the anther to the stigma. Most provide certain visual effects to produces fragrance in the morning. orchids are cross-pollinated, attract the insects. It is believed that sesquipedale and requiring some pollinators to transfer the ultraviolet and visible light­ Brassavola nodosa, both being the pollen from one plant to another. reflecting patterns of the flower, moth-pollinated, produce their There are many extremely complex provide such an attraction. Once a fragrances at night. and ingenious mechanisms to ensure flower is pollinated, its colour and effective pollination. In this article, I image change so that the flower is no Once the pollinators are will discuss how some of the species longer attractive to the pollinator. attracted to the flowers, many orchid in our collection are pollinated in These reflective patterns, especially species have other means to ensure their natural habitats. those of the UV range, cannot be successful pollination. One example detected by the human eye. is the ejection of pollinia by GD . • Owing to the differences in -rOI11 tnattOfl ~~~o~f~:!~~among pollinators, orchid flowerspollinatedby .SffiS different groups of Mechanl pollinators have different colours. For example, bee-pollinated flowers such as Of Arundina graminifolia and •d Dendrobium crumenatum, may be -rc .. , s of several colours, but are seldom if 0 .J. ' h ~ ever red. Butterfly pollinated orchids such as Disa unijlora are mostly pink, red, and yellow. Those pollinated by moths such as Most orchids are cross­ Angraecum eburneum are cream, pollinated by animals such as ants, white, and pale green in colour. The bees, beetles, wasps, moths, colour of the flowers pollinated by butterflies, flies, and birds. flies such as Bulbophyllum gusdorjii is very variable. Orchids One way in which a species pollinated by birds, for example, attracts its pollinator is by the Dendrobium secundum are bright production of nectar. The sugary yellow, red and pink, and are liquid may be produced in spurs as in sometimes tubular in shape. species of Angraecum and Aerides or in nectar tubes as in Cattleya. The Certain orchid species possess nectar produced by the host plant is some movable floral parts. The insect food for the pollinator. While pollinator is attracted to the flower collecting nectar, the pollinator by the movement of such parts in an inadvertently transfers the pollen air current. An example is from one plant to another. Bulbophyllum barbigerum from Africa. Its hairy lip is very sensitive The lip of an orchid flower is to the slightest air movement. often its most attractive part. It is adorned with decorative and To attract specific pollinators, sometimes stunning masses of calli. orchid species produce a large These calli and other floral parts may number of compounds that generate contain unicellular trichomes odours and fragrances. For example, ("hairs"), papillae, and scales which many of the fly-pollinated produce starch, proteins, oil drops, Bulbophyllum species smell like fragrances, and other substances to rotting meat, whereas the sweet attract the pollinators. Examples can smelling Dendrobium crumenatum be seen on flowers of Cymbidium, is bee-pollinated. The odours and Stanhopea, Oncidium, perfumes of these orchids are Dendrobium, Coelogyne, Vanilla, blended in such a way that each and others. While feeding or orchid species attracts only one or a scratching and gnawing at the calli, few species of pollinators. the pollinators may pollinate the plant. 2 Depending on the activities of the pollinator, time of scent production varies among species. For

6 territory that has no natural pollinators, the ability to self­ pollinate allows the plant to establish in the new territory.

Certain species have both cross-pollinated as well as self­ pollinated varieties. Some examples that can be seen in our collection are Spathoglottis plicata, A rundina graminijolia, Phaius tankervilleae, and Cattleya aurantiaca.

6 the pollinarium. The ejected So, next time when you visit pollinarium sticks to the apex of the the Orchidarium (the part of the abdomen. When the bee visits a National Orchid Garden where our female flower, the pollinarium is species collection is displayed), look placed on the stigma. out for some of the species mentioned in this article. Try and Flowers of the genus find out how these species are elata, the national flower pollinated. It will add a new of Panama, have a hinged lip. When a dimension to your understanding of euglossine bee lands on the lip of the this fascinating family of plants. And 4 flower, the hinged lip tends to if you are lucky, you may even be Catasetum. Catasetum is one of counterbalance and throws the bee able to spot some of the pollinators those unusual orchid genera that has against the column. As a result, the in action! separate male and female flowers. pollinarium is attached to the thorax When a euglossine bee visits a male of the bee. The bee inserts the Dr Yam Tim Wing flower of Catasetum, it touches the pollinarium in the stigma of another Senior Research Officer/Orchldology antenna of the column, triggering off flower. the ejection of the pollinarium. The pollinarium sticks tightly to the back Only a small percentage of of the bee. If the flower the bee next orchid species self-pollinate. Some visits is female, it will, on backing out orchids self-pollinate while the buds of the flower, automatically cause the are still closed. An example in our pollinarium to be inserted onto the collection is Dendrobium stigma. Another interesting mirbelianum. Self-pollination is I. The calli on the lip of an Oncidium - the calli made possible by autolysis of the masses provide certain visual effects to attract its mechanism can also be seen in some insect pollinator. rostellum preceding pollination, thus Cycnoches species (also with 2. A elides lawrenceae- nectar is produced in the separate male and female flowers). allowing the pollinia to come into spur of thls beautiful species. As the flowers of this species do not contact with the stigma. Although 3. Male flower of Cycrwches pentadactylon var. resupinate, the lip is situated above self-pollination results in reduced penwianum. the column. When the euglossine bee variability and genetic stability, it is a 4. Angraecwm leonis- a species that is pollinated by moths. lands on the lip of a male flower, the means of ensuring pollination when and/or where it may not take place. 5. Seed pods of Dendmbium mi1·beliannm formed lip is depressed. As the abdomen of by self-pollination. For example, when seeds of a the bee touches the tip of the 6. A variety of SpatJwglottis plicato. that self­ column, it triggers off the ejection of species are being carried to a new pollinates.

7 Singapore is Dieffenbachia paludicola which is highly regarded THE as a "good luck" plant. The other genus that flourishes well in the AROID shade is Homalomena. Homalomena sulcata and H. wallisii are two rather ornamental HOUSE species that are easy to maintain and do well as house plants. Introduction Creepers & Climbers A new addition to the Gardens is the aroid collection which was put Most Philodendron, together for display in the recently Monstera, Epipremnum and opened Aroid House. The Gardens Syngonium are climbers and has at the moment, a modest creepers which grow exceptionally coll~ction of 29 genera and some 160 well in diffused light. Philodendron species and cultivars. These plants means "tree loving." ln nature, were acquired either as gifts, members of this genus creep on tall exchanges or purchases through the trees in search of light. They are years. Aroids belonging to the family best known for their diverse leaf industry. Its popularity in the recent Araceae are one of the distinctive shapes. 1n some species, the juvenile years has further risen as many and interesting groups of plants and mature leaves are completely effulgently coloured spathes have equivalent to the orchids and dissimilar. Some Philodendron been introduced into the market. bromeliads. Unlike bromeliads which cultivars like Philodendron "Black While Anthurium bakeri has an are found primarily in Central and Cardinal", P "Moonlight" and P spadix bearing interesting red South America, aroids like the "variegata" produce very lovely berries, A. scandens has white ones. orchids are cospomolitan except in colours which enthral many a Anthurium thrives best in well the arctic, high alpine regions and gardener. One creeper that most of drained soil mixes and in bright but extreme desert areas. The majority us are familiar with is Epipremnum not in too sunny areas. occur in the tropics or sub-tropics. aureum (locally known as "money plant"). This can be spotted in shady "Keladi" An aroid is distinguished by areas along some of the roads in the presence of a spadix (flower­ Singapore. This species exhibits the Colocasia, Xanthosoma and bearing spike) surrounded by a phenomenon wherein as a creeping Alocasia are closely related; the first spathe (large leafy bract) which is groundcover, the leaves are small but two especially are well known as root peculiar only to this family. What when allowed to climb on a tree or crops. They are known as taro or intrigues the grower is the bizarre tall post, the leaves become gradually yam to some while the locals called leaf shapes and inflorescences found bigger, eventually exceeding half a them "keladi." The common in this family. Aroids may be aquatic metre in length. Colocasia esculenta prefers to grow or terrestrial and can be herbs, in damp areas or shallow water while climbers, creepers or tree-like plants. Petite Foliage Alocasia macrorrhizos, a species Generally, aroids prefer slightly moist with inferior tubers, thrives on drier and shady areas. The aroid that has the most land. Yet as a specimen, Alocasia exquisite and dainty foliage is macrorrhizos can be quite Low Herbs indisputably the Caladium. This imposing, growing to more than 3 genus has numerous hybrids with metres even on poor soil. Other Aglaonema, Dieffenbachia very charming and delicate leaves. It lovely species of Alocasia used for and Homalomena are herbaceous can grow in bright areas but does ornamentals include, A. denudata, plants which can be rather attractive better in slight shade. Caladium A. sanderiana, A. cuprea and A. house plants. Aglaonema does well lindenii which has green leaves with lowii. A. denudata is a native of in deep shade whereas prominent white veins is an ideal pot Singapore and although fast Diejfenbachia prefers more light. plant. disappearing can still be fo und in its Aglaonema commutatum, has natural habitat. bright yellow to red, berry-like fruits Dazzling spathes which can be quite captivating. Continue to Page 13 When handling Diejfenbachia Anthurium means "tail (Dumb Cane), one must exercise flower." It is the largest genus in the 1. Anthwimn baked caution. The tissue of this plant family with more than 700 species, 2. Jlomalmnena sulcata renders one temporarily dumb when and hundreds of cultivars and 3. Anth1t!"iwn andmeanmn ':Rub,·um" consumed. The symptoms are a hybrids to its credit. They are either 4. Philodendmn "Black Cardinal" burning sensation and swelling of the terrestrials or epiphytes. 5. Colocasia esC1tlenta tongue, mouth and throat. However, Anthurium is grown for its stunning 6. Aglaonema conwuttalwn Diejfenbachia with lots of variations spathe which is a very sought after 7. Calad;um lindenii in the foliage is a great-looking house "cut flower" in the floriculture 8. Typhmwdonnn linleyanwn plant. A favourite of the Chinese in

8 2

5

6 7 9 To most people, pineapple is a They can often be spotted as vase­ familiar tropical fruit. Not many like or tank-like epiphytes, perched would associate it with the on branches of rain forest trees. ornamental plants popularly called They also inhabit rocky cliff faces Air Plants, Spanish Moss, Earth Stars while others grow on the ground in or Fingernail plants. These, just like deserts or on mountain tops. One the pineapple, belong to a plant species, Tillandsia recurvata, has family called Bromeliaceae and are even been found growing happily on commonly referred to as bromeliads. telephone wires.

Bromeliads are characterised by their bizarre forms. Their sizes may range from tiny moss-like plants .. as in some Tillandsia to gigantic forms as in Puya. When not in bloom, they often appear as a tuft of foliage or as a rosette of wiry, strap­ like or sword-like leaves. The bases

Except for one species that is of these leaves may overlap and be native to Africa, all wild bromeliads watertight, forming a tank or are restricted to the New World, reservoir that collects water and extending from southern United detritus or they may be open, · States of America and Mexico down allowing free drainage of excess to the southern parts of Argentina water. High up in the canopy of the and Chile. The main concentration of tropical rain forest in the Amazon, bromeliads is distributed in Mexico, many tank bromeliads actually the Antilles, Costa Rica, eastern and provide the essential micro-habitats southern Brazil, the Andes of fo r frogs and other organisms that Colombia, Peru and Chile. live off the ground.

In the wild, members of The foliage of some bromeliads come from a wide range bromeliads may be coloured green , of habitats and climatic conditions - yellow, brown, red or beautifully from the lowlands of the tropical rain patterned with longitudinal stripes. forest, semi-deserts and deserts to In other instances, it may be the icy regions of high mountains. mottled or spotted, cross-banded or 10 reticulated. Some fine examples of coloured and patterned foliage are demonstrated by Cryptanthus zonatus, Guzmania lindenii, G. musaica, G. vittata, Neoregelia carolinae var tricolor; N. mw"'mmrata, Vrieseajenestralis, V gigantea and V hieroglyphica. Even in their non-blooming state, these bromeliads can be the pride of any grower. The inner leaves of many species (e.g. some Neoregelia, Nidularium) assume brilliant contrasting colours of different hues during flowering and gradually regain their normal, green colour after flowering. Other species, especially those found in very dry habitats, have thick leaves that are equipped with teeth and spines on their edges. Examples are found in many species of Dyckia and Hechtia.

Another outstanding feature of bromeliads is their prominent bracts and colourful flower spikes that frequently outshine the small flowers. The flowers of bromeliads are typical flowers with all parts in threes. There are three , three and the stamens are arranged in two circles of three each. The ovary is formed of three fused carpels. In most bromeliads, a bloom often means the gradual death and the loss of the plant if offshoots are not produced from the base or from leaf-axils of the parent plant. Offshoots are an easier alternative of propagating bromeliads when seeds are not formed. For species that have successful fruit-set, the berries or capsules formed can be vividly coloured and remain so for several months. This is another unique feature that attracts bromeliad enthusiasts.

Care and Cultivation

With such a wide range of conditions under which bromeliads are found, it is a challenge for any grower to try and simulate the conditions of each species under his or her care. Part of the fun of growing bromeliads is to learn about the habitats of the species and to provide the required conditions if best results are to be obtained. Continue to Page 12 I. Yuen·Peng McNeice Bromeliad !-l ouse 2. A "water-tank" fonned by overlapping rosette leaves 3, 4 & 5. Prominent bracts and colourful flower spikes

11 Continue from Page 11 Bromeliacls The appearance and structure of bromeliads often give clues as to their cultural needs. Those with vividly coloured foliage usually need considerably more shade than those heavily furnished with grey or whitish scales. Such scales are a natural defense against intense light and drought and indicate that these grey and white plants grow in exposed areas of little rainfall but of high humidity. Many tillandsias, including Spanish Moss and the so­ called Air Plants show this habit and they absorb moisture directly from the air. These plants under cultivation would enjoy daily misting with water on their foliage. Bromeliads with thin textures and rather soft, green foliage would tend to have a preference for shade and high humidity and have a need for keeping the tank/reservoir formed by the bases of leaves filled with water all the time. These bromeliads are inhabitants of areas with high precipitation. However care must be taken however not to leave the water stagnant for too long, as mosquitoes might breed.

The absence of well-developed tanks/reservoirs and the presence of 3 tough, succulent and spiny foliage suggests that the species in the wild probably grows under dry conditions. The Collection at the To avoid rotting, the roots of species Singapore Botanic Gardens of this description should not be kept constantly wet and watering should on cork bark, slabs of tree fern bark, A good way to trigger off an be sparingly carried out. drift wood or wooden frames. interest in Bromeliads is to visit the Besides judicious watering, small collection in the Gardens. This Potting mixes for bromeliads doses of a liquid fertilizer can be collection, located in and around the vary according to the needs of the applied to the plants from time to Yuen-Peng McNeice Bromeliad various groups. In general, mixes time as a foliage spray. House in the National Orchid Garden must be acidic rather than alkaline, consists of about 15,000 plants from must drain freely, and for epiphytic More often than not, non-tank 800 species and cultivars. A visit will kinds, they must contain a good bromeliads perish due to root rot inspire and give you an idea of the amount of organic matter. Most caused by over-watering. Many range of form and colour of these bromeliads enjoy fairly dry, sunny species are known to be sensitive to wonderful plants that have travelled and airy conditions. The cultural copper, iron and other metals. Do not half the world to be with us. needs of bromeliads in many ways use copper wires to attach labels to resemble those of epiphytic orchids. bromeliads. Alkaline soil and water For those green-leafed bromeliads should also be avoided. Over­ Tay EngPin that can take to pot culture, e.g. exposure of shade-loving bromeliads Curator/Horticulture Aechmea, Billbergia, Guzmania to intense light would result in and Vriesea, an open-textured, lime­ discoloration and leaf-scorch while free mixture consisting of one part not providing enough light for those

peat moss or shredded leaf mould, grey and white bromeliads will result I. Coloured foliage one part coarse sand or perlite plus in unsatisfactory growth. 2. A flowering Painted-fingernail bromeliad some organic matter is ideal. Truly 3. Inner leaves assuming brilliant colours close to epiphytic bromeliads can be grown flowering

12 Continuejnnn Page 8 THE AROID HOUSE Aquatics and Semi-aquatics

There are a number of aroids that make rather majestic specimens in ponds while others are suitable for marshy areas or by the edge of ponds. Typhonodorum lindleyanum, a native of resembles a banana tree and can grow to a height of more than 4 metres. Philodendron bipinnatifidum, a climber thrives well both on dry land or in water and is suitable for both sunny or semi­ shaded areas.

Pistia stratiotes or water lettuce is the only floating and stemless aquatic aroid. This plant which can grow to a diameter of 20 em is spongy in texture and bears small white hairy spathes in the centre of a light green rosette of leaves.

The genera, Anubias and Cryptocoryne are small plants, cultivated largely in aquariums although they can be planted in ponds, too.

The genus, Spathiphyllum favours wet grounds and does very well at pond margins. The 3 inflorescence is quite similar in appearance to that of Anthurium, !. Pistia stmtiotes but the white spathe emits a strong 2. Spathiphyllum cannifolium and sweet fragrance. 3. Aconts calamus 4. Amo?plwpltallus paeoniijolius Acarus calamus or Sweet Flag is an aromatic herb that originated from temperate Asia and India. Over the centuries, it has spread to most parts of the world and it is still highly regarded as a medicinal plant. It looks unlike a typical aroid looking more grass-like. When crushed, the leaves give a light and sweet aroma.

Bizzare Blooms paeoniijolius or Elephant yam, a A very fascinating and unique native of is widely aroid, Amorphophallu,s, can be grown for its edible corm. A. found in the Aroid House. Members titanum, reputed to have the tallest of this genus usually bear only one inflorescence of any herb, is also leaf at a time. The inflorescence is planted in the Aroid House. often massive and fleshy with a spreading spathe and a foetid Andrea Kee appendix. Amorphophallus Assistant Manager/Plant Resource Centre

13 By defmition annuals are the nurseries. (Locally grown or plants that complete their life cycle imported from they are within one year or less. They are fast reasonably priced at between $6 to growers and being heavy feeders and $15 per pot). However, you can grow ephemeral are regarded as high a wide range, and all the year round maintenance plants. These plants too. normally lose their vigom after flowering and will have to be Selection replaced by younger plants at this time. Flowering annuals nevertheless Annuals are usually grown are popular among avid gardeners. from seeds which are sold in They can be planted in beds and colourful packets in the gardening troughs, in pots, window boxes and section of departmental stores or in hanging baskets. As they are short­ plant nurseries. Few like the coleus, lived, they can be planted as fillers, chrysanthemum, dahlia, petunia, i.e. mixed among the more salvia and busy lizzie, can be AHHN4/8 permanent plants in a planting bed. propagated from cuttings. While some annuals like the celosia and Growing annuals may appear marigold take between 90 to 100 cumbersome and costly to some, days to reach full flowering from lH/foNr however they yield quick dividends seed, others like the chrysanthemum and the garden is always different normally require between 120 to 180 with fresh flowers and new colours. days, depending on the cultivar. (#tJrdeH It is obvious that annuals which are Sowing and Seedling Care

There are several ways of starting plants from seeds. The conventional way is to sow seeds on a propagation tray of a suitable rooting medium like vermiculite, sand, or a mixture of sand and coco peat.

4 To prevent etiolation it is important to bring the seedlings out from the shaded propagation house to benches where there is sufficient sunlight. Ensure that watering is adequate and to boost growth, fertilise the seedlings with a dilute easily planted for a massed colour liquid fertiliser (check the I. Tithonia effect, bring life to shopping malls instructions given on the fertiliser 2. Tol"renia (foreground) and Coleus in a garden and meeting places. In the temperate pack for the correct dosage for setting. countries they are predominantly seedlings). 3. Ornamental Chilli displayed in parks and gardens 4. Marigold during spring, summer and autumn. Another convenient way is to In Singapore they surface during the use netted Jiffy-7 peat pellets or festive seasons like the Chinese New 'pots'. Soak the compressed peat Y~a r. Even then only a few popular 'pots' in water and arrange them in types, like celosia, chrysanthemum, the propagation tray. Plant two to marigold and dahlia are available in three seeds to one peat 'pot'. The

14 advantage of using this method is that there is little disturbance to the JEWELS OF THE WATER roots as the seedlings are transplanted together with the peat Introduction Nymphoides, due to their to planting beds or pots. appearance, are often mistaken by The varied landscapes of the many as belonging to the water-lily When seedlings have Gardens add to the joy and pleasure family Nymphaeaceae. Botanists developed two or more leaves they of visitors. A unique attraction is the recognised this similarity in overall are ready to be transplanted or waterscapes. These are graced by a appearance by bestowing the name pricked on to individual pots fascinating group of plants, the Nymphoides, meaning, 'resembling containing a suitable potting mix for aquatics. the genus Nymphaea.' The annuals. Imported potting mixes are similarity in the leaves and manner of generally light, consisting of sand, Some aquatic plants grow growth is deceiving because careful peat, and perlite. Burnt earth or rooted in the mud and are examination of their blooms vvill sterilised topsoil can be incorporated completely submerged. Others quickly dispel any belief that to give the mix more weight, or used rooted at the bottom may produce Nymphaea and Nymphoides are alone. The selected mix should be floating leaves, with their flowers kin. The latter belongs to the well-drained yet moisture-retentive. borne above the water. Yet others gentian family, Gentianaceae. float on the surface with their dense Pinching and staking tuft of fine roots trailing in the water. One species is Nymphoides All these plants are completely indica, commonly known as ' Except for celosia, most dependent on the water and will not snowflake'. From its underwater annuals require pinching or the survive on land. rhizomes, long leafstalk-like stems removing of terminal shoots or appear. Sterile stems bear a broad growing points to encourage Other aquatic plants are heart-shaped floating leaf at the top branching and bushy growth. This is happy in the border zone between while the fl owering stems bear one first carried out when seedlings are 8 water and land. They grow on wet or more leaves and pure white em to 10 em tall, and regularly done soils or in shallow water and are blooms with yellowish centres. for every branching until a suitable often referred to as marsh plants. Individual blooms remain open only form is established and the plant is They have both shoots and fl owers in for one day. ready to flower. the air, and some of them are able to withstand short periods of drought. Nymphoides are delightful for Tall and bushy plants require It is often not possible to make a pools and other still waters. They supporting canes or stakes. Tie the clear division between the plants of give little trouble and produce long stems loosely to the stakes. Continue the water and marsh plants. displays of blooms. They can either supporting the stems as they grow. be grovvn in containers or directly in The plants the soil bottom. They give their best in rich, rather heavy soil and thrive in full sun. Propagation is by division or Care The waterlilies are the most by seeds. common group of aquatic plants Most annuals require strong found in the Gardens. They are There is probably no other sunlight, adequate watering and popular as they have strikingly plant held in such reverence in the regular fertilising. Use fertilisers high beautiful flowers and because they East as the lotus, Nelumbo in nitrogen for initial leafy growth are easy to grow. Their generic name nucijem. This plant has thick and high in phosphorus and Nymphaea is from the Greek word rhizomes and large circular plate-like potassium for flowering. Organic nymphe, meaning a water nymph. leaves with the stalks attached fertilisers like Hortimeal and Nitrosol Water-lilies are propagated by seeds underneath at the centre of the and chemical fertilisers like and rhizomes. Some species have blade. Both the leaves and flowe rs Phostrogen, Gaviota, Hyponex, and viviparous ability with new plants are normally raised high above the Nitrophoska are some of the many sprouting from the leaf stalks. The water on stout stalks, the flowers suitable fertilisers available in the rhizomes and seeds of some species mostly overtopping the fo liage. The market. are used as food locally. usually white or pink fl owers are very attractive and fragrant. The funnel­ Inspect the plants regularly for Water-lilies need exposure to shaped 'seed-pods' are flat-topped insect infestation and manually full sun and still or sluggish water. with holes containing a large seed­ remove insects if present. If They do not prosper in streams with like nut each. Frequently they are chemicals have to be used, apply the any appreciable flow or in pools with dried, bronzed or silvered and used least toxic types like soap solu tion, fountains splashing onto them. They as ornaments. white summer oil or plant-derived are gross feeders, needing rich soil pyrethroids. preferably on the clayey side. One According to Hindu belief, good mix is fertile topsoil enriched valleys, hills and rivers were formed with bonemeal and a slow release from the petals of a huge lotus Jennifer Ng fertiliser. The Gardens showcases a flower by Brahma the creator of the Assistant Director, Education collection of water-lilies with red, Universe. An Indian fable holds that blue , yellow, white and pink flowers. Continue to Page 16

15 Continue from Page 15 leaves, petioles and inflorescence are used in the Orient. The flowers arc cooked as food. Elsewhere it has about 2.5 em in diameter and have JEWELS been used for making paper and petals blotched at their bases with OF cardboard. purple. Water hyacinth grows best in Arrowheads are useful for THE WATER nutrient rich waters. It requires permanent plantings at the margins sunny areas and a comparatively still of ponds, streams and other water the lotus flowers obtained their environment. It is best grown in bodies. They can also be grown in reddish colour by being dyed with water not over 30 em deep so that tubs and containers to complement the blood of Shiva, when Kamadeva, the soil that supplies needed water lilies and other lower-growing the god of love, wounded him with a nutrients is not far away. It increases aquatics to provide a welcome love arrow. To the Buddhist the rapidly by natural offsets. variation in height , leaf-shape and lotus flower symbolises Man with his flower pattern. They require fertile, head held high, pure and undefiled in Thalias, of the family loamy soil and succeed in sun or the sun while his feet are rooted in a Marantaceae, are confined to the partial shade in water from 2 em to world of experience. It is a symbol of tropics of the Americas and Africa about 45 em deep. Propagation is beauty and a sacred seat of Buddha. and in nature chiefly inhabit swampy usually by division. He was believed to have been born in forests. The name commemorates the heart of a lotus flower. This the sixteenth-century German In the Botanic Gardens there are a few m·eas where you will be able to see could also be the sacred lotus of the physician and naturalist Johann Thal. aquatic plants. These include the A mid Nile, which is no longer found there. They are herbaceous perennials with House, Marsh Ga1den, Sundial Ga1den, long-stalked, calathea-like, all-basal Symphony Lake and Eco-Lake. Take your Lotus can be planted in mud leaves and purplish, violet or blue time to enjoy the beauty of these plants. bottoms or in containers of rich soil blooms. The stalks enfold each other where their rhizomes are covered toward their bases and function as Camelia Marican & Alan Tan with 30 em to 90 em of quiet water. Assistant Managers, pseudostems. The spikes bear Singapore Botanic Gardens Mgmt . They need a sunny location and for flowers in two vertical rows and are their best development , ample space with bracts that fall before the fruits to spread. Propagation is best by mature. seeds. Thalia dealbata, a native of The water hyacinth, swampy woods from South Carolina Eichhornia crassipes, is an aquatic to Missouri, Florida and Texas, has herb native to South America. It is purplish blooms that are attractively generally free floating but in shallow coated a powdery-white. Thalia waters may root into mud bottoms. geniculata, on the other hand, It forms broad, rosette-like clusters differs in having looser, pendulous of leaves with much-swollen spikes with markedly zigzagged leafstalks and great masses of long, stalks and blooms that are not coated dangling, freely-branched roots. The a powdery-white. flower spikes are erect and arise from the centre of the plant. Thalias are useful as graceful flowering decoratives for boggy When first introduced to the places and shallow ponds and pools. USA from Venezuela in 1884, it was They require lightly shaded or sunny regarded as an innocent and most locations and thrive in fertile soil that attractive water ornamental with its contains generous amounts of showy bluish flowers. But the plant organic matter. They can be soon became a menace reproducing accommodated in large tubs or remarkably fast choking waterway, containers or can be planted directly affecting both transportation and fish into soil bottoms in up to 1 m of population. On the other hand, it is water. Propagation is by seeds or considered useful because of its division. ability to absorb various elements from the water, hence functioning as Sagittaria sagittifolia, or a water purifier. better known as the arrowhead is a variable n~t ive of Europe and Asia. A Chinese resident brought The name Sagittaria, from the Latin the water hyacinth into Singapore sagittarius (armed with arrows) from Hong Kong in 1903 and grew it alludes to the shape of the leaf in his garden at Balestier Road and blades. The bases of the arrowhead from there it was later brought to the are under water with the roots I. Nymphaea cultivar Botanic Gardens. Chinese villages at anchoring them to the soil bottom. 2. Nelum.bo mtcifera 3. Eichhomia cmssipes Bukit Timah Road later grew it for Arrowheads have milky sap and 4. 17wlia dealbaiCI, an inOorescence showing zigzag feeding pigs . In Java the young formed edible tubers which are much stalks

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