Gardening with Wilson

I first came across a medicinal plant that is called ‘ulam raja’ when I was doing a research project on plant antioxidants during my Food Science and Technology undergraduate days in the National University of Singapore. Thanks for my Malay friend, Hidayat, he was the one who brought me to Geylang Serai wet market on several Sunday mornings to search for vegetables and plants that are consumed by the local Malay community.  I have not seen it being put up for sale in most other markets. In the local market, bundles of fresh, young and tender tips of this plant are put on sale. They wilt quickly, however, under our hot weather here.

Botanically known as Cosmos caudatus, it is sometimes called ‘wild cosmos’ by locals here but it is mostly refered to via its Malay name, ulam raja, which translates into ‘king vegetable’. Native to tropical America, it was first introduced to Philippines via the Spaniards, according to Plant Resources of South East Asia (PROSEA). The pinnate to pinnatipartite leaves of this plant are consumed as a leafy vegetable, usually in the raw form, but sometimes also cooked and mixed with coconut sauce and chillies. It constitutes as one of the more common raw plant leaves eaten a salad-like form, called ‘ulam’ by the local Malay community as well as those in Indonesia and Malaysia.

For the uninitiated, the leaves of ulam raja tastes raw and somewhat astringent. When crushed, the leaves emit an odour that is reminiscent of mango. It is considered as a medicinal herb which is believed to possess the ability to cleanse the blood and strengthen bones due to its high calcium content. From my research, a preliminary one which was done with my then postgraduate colleague, the dried leaves of this plants contain high amounts of potent antioxidants. The results of our work was published in the following paper:

Shui G, Leong LP, Wong SP. (2005) Rapid screening and characterisation of antioxidants of Cosmos caudatus using liquid chromatography coupled with mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci. 827(1):127-38.

The plant itself can grow quite tall, up to 3 m tall but is an annual or a short-lived perennial herb. It produces dainty, attractive pink flowers when mature. It should not be confused with the yellow- and orange-flowered Cosmos sulphureus as both species are similar vegetatively and have some vernacular names (randa midang in West Java) in common. The latter are more important as ornamental plants that are a common feature during Chinese New Year.

The ulam raja plant was once difficult to find in Singapore. It can sometimes be found naturalised in abandoned kampongs or wastelands. Occasionally, one is able to find a colony being grown by a Malay resident in a community garden. A few years ago, it was almost impossible to buy pots of this plant. Only recently, I discovered World Farm, a Singaporean wholesale nursery stocking some pots of it for sale to the public. I managed to get some young plants that were weeded out from a colleague’s park a couple of months ago.

This plant is rather easy to grow. It thrives in a sunny spot outdoors with well draining, fertile and moist soil. It is a big drinker and demands a constant supply of food. Under optimal conditions, it grows quickly, flowers and sets seeds very readily. Plants self seed easily and can quickly become a weed in a garden. Harvesting of leaves can commence once plants are 6 weeks old and subsequent ones can be done every 3 weeks. Regular harvesting will stimulate the production of useful and edible foliage and helps to delay flowering.

I was given a division of Orchidantha siamensis by a fellow collector a while ago who knew I was interested in plants that are classified in the order Zingiberales. There is only one genus, that is, Orchidantha, in the Lowiaceae family. This genus consists of about five to eight species of plants that grow in the wet understorey of the lowland forest and are native to Southeast Asia and some Pacific Islands.

The genus name is given due to the orchid-like appearance of the flowers produced by these plants. Flowers are usually produced via a subterranean inflorescence and are often hidden away. One of the petals in each flower is enlarged to give a large lip-like structure similar to what is seen in a true orchid. Flowers of one species, Orchidantha inouei of Borneo emits the smell of dung in order to attract small dung beetles as their pollinators! The plant I have freely flowers and thankfully, the smell of its flowers can only be detected when one really goes upclose to them!

I particularly like the Orchidantha as it is perhaps the most shade-tolerant group of plants I have come across so far. Many foliage plants introduced in many houseplant and indoor plant books cannot match it in terms of the ability to grow and thrive in deep shade often encountered in the indoor living environment. It seems to be also able to tolerate dry air rather well too. From this, I reasoned that they also make good candidates for planting in very dim areas in an outdoor garden.

Best grown and appreciated as foliage houseplants that confer a lush tropical feel, Orchidantha species are herbaceous perennial plants with a clumping growth habit. New growth rise from a rhizomatous underground stem. Leaves are lanceoate in shape andhas several pairs of longitudinal veins parallel to the distinct midrib.

I noticed Orchidantha is best grown in a very shaded area as even rays from filtered sunshine can bleach the leaves, giving them a sickly yellow colour. Intense sunshine will burn them. They prefer to be grown in soil that is rich in organic matter, open and kept moist at all times. Avoid growing them in a windy area as constant air movement can dry plants out. Propagation is easy via division of large clumps.

Orchidantha, apparently, have medicinal and folk uses. The scorched leaves of Orchidantha fimbriatum (syn. O. longiflora) are pasted on the back and chest to relieve chest and back pains. Leaves are sometimes used to wrap food in cooking.

At present, Orchidantha is still difficult to find in local nurseries but I believe its usefulness as a foliage plant for growing in very shady areas, once discovered, will greatly call for a demand for plants to be made available to the nursery trade.

Selected species of conifers grown in overseas plantations appear to be almost indispensable must-haves for Christmas. In Singapore, Nordmann fir (Abies nordmanniana, shown in photograph below) and noble fir (Abies procera) are two popular conifers that are imported and sold in local nurseries before the festive season. Noble firs emit a citrus-like aroma and tend to be bushier whereas Nordmann firs are exhibit a more distinctive layered look and a droopier look, with more spaces between the branches than the former.

Many Singaporeans buy live Christmas trees because the delightful fragrance from the aromatic oils in the leaves that permeate the entire home environment. Live Christmas trees are entirely biodegradable and can be turned into woodchips for use as mulch after they decline.

This year, in HortPark’s Lifestyle Corner, we put up a Christmas tree corner where visitors can pose for photographs. We have two Christmas trees, one is a common Nordmann fir while another is a blue spruce. The latter is a relatively new introduction we bought from Candy Floriculture Pte Ltd that is known by its botanical name Picea pungens glauca ’Baby Blue’ which happens to be a cultivar grown from seed harvested from a blue spruce orchard at West Montrose Farms Ltd (Source – http://www.babybluespruce.com/index.htm). Shown below, it has beautiful bluish green leaves that are not commonly seen in the local range of imported Christmas trees.

Imported Christmas trees these days come in both the usual cut form, as well as, potted trees, complete with roots and growing media. The latter type of tree is probably easier to maintain as water is stored in the soil compared to having to watch a reservoir of water placed at the base of a cut tree. In Singapore, there is always a risk of mosquito breeding in reservoirs containing stagnant water. Hence it is necessary to put anti-mosquito granules in water reservoirs for cut Christmas trees.

It is unlikely that these imported potted Christmas trees can survive and even grow in the long term in Singapore due to differences in climate as these trees come from temperate regions that experience frost. It is during this time that trees get their annual rest which cannot be observed in tropical Singapore. Trees may not die immediately but they should slowly decline.

For those of us who are looking for tropical alternatives that will thrive in Singapore, there is actually a limited range of conifer species to choose from. However, there are two major drawbacks associated with the use of these trees. Most of these species do not have aromatic foliage and need to be placed in a location with good light to prevent leaves from turning brown and falling.

Shown in the outdoor display in HortPark’s Lifestyle Corner on the Timber Deck (picture above), we have put forth a selection of Chinese juniper cultivars (Juniperus chinensis) which adopt different growth habits, ranging from those with erect and conical canopy shape to those with sprawling ones. Some have leaves that are tipped with gold or even blue. Two other conifers for consideration include the Oriental Thuja (Platycladus orientalis) and Norfolk Island Pine (Araucaria heterophylla).

Last weekend had been a really busy one for me. On 19 Dec 09, a Saturday, a day before the gardening Sunday at HortPark, I was involved in delivering a talk entitled ‘Edible Gourds for Your Garden’. This was a last minute talk that was put together to replace Boon Kiat’s talk as he was not able to give his cacti and succulents talk due to compassionate reasons.

In this talk, I shared with my audience one of my favourite group of edible plants that I have tried my hands growing them before. As the term ‘edible gourds’ suggests, my talk attempted to introduce the range of fruited vegetables that are members of the Cucurbitaceae family. Some familiar members of this plant family include cucumbers, bittergourd, luffa and bottlegourd. These constitute some of the most rewarding and easier species to grow here locally.

In my talk, I shared some tips based on my personal experience as well as problems encountered during the growing of some of these gourds in my community garden. The audience also got to know the sources to go if they are keen to purchase some seeds to grow some of these plants in their home gardens.

In the slide above, my audience got to know that some cucurbits have medicinal uses. They include the following plants:

1. Five-leaf ginseng (botanical name - Gynostemma pentaphyllum) is called ‘绞股蓝’ or ‘ jiaogulan’ in Chinese, which is  possesses adaptogen and antioxidant properties.

2. Bittergourd, especially those with smaller fruits are said to have hypoglycaemic properties by many Chinese Singaporeans here. Fruits are juiced and the beverage drunk.

3. Winter melon slices are often sold as sugared, dried slices, which are used in herbal teas for their purported ‘cooling’ effects.

4. ’Arhat fruit’ (botanical name - Siraitia grosvenorii) is called ‘罗汉果’ or ‘luohan guo’ in Chinese where its dried fruits are used in Traditional Chinese Medicine.

5. Spiny bittergourd (botanical name - Momordica cochinchinensis) - The red aril around its large seeds are cooked with rice in Vietnam and the seeds which resemble the turtle shell (called ‘木鳖子’ or ‘mubiezi’ in Chinese) are also used in Traditional Chinese Medicine).

In another slide, I showed my audience two other species of species which commonly occur as weeds in Singapore which are largely ignored. Coccinia grandis also called the ivy gourd is a vine that produces white, star-shaped flowers and edible fruits that are sold in Little India. Another is a species of Melothria, which produces small yellow flowers and cute, oval fruits.

Despite the rain, locality of this library in the East as well as proximity of the date to a major festive day (that is Christmas), I saw only a handful of gardeners who made it a point to attend my talk at Tampines Regional Library’s Auditorium and I am very grateful for their support. I was happy to see a few familiar faces amongst the audience and one of them was Ms Nancy Ong who is a community gardener currently residing in Marine Parade where she showed me the fruits of her labour. She has successfully grown watermelons and honeydew in her community garden in her condominium.

Note that the pictures shown in my presentation slides still belong to their respective owners and are used then for illustrative purposes only.

Ho! Ho! Ho! HortPark Christmas 2009 was an event organised by my colleagues from HortPark to spread the Christmas cheer on 20 Dec 2009. Singapore finally had its long-awaited, first bazaar dedicated to gardening hobbyists. It was a rainy afternoon and that did not deter gardeners from all over the island to come to HortPark.

Christmas shopping ranked high on the agenda of gardening enthusiasts as they trawled through the 20 participating stalls for interesting plants and offers throughout the 4-hour gardening bazaar held at the Exhibition Gallery in HortPark. Motivated by the good response and positive sales, many of the vendors have expressed their continued support in subsequent Gardening Bazaars to be held at HortPark. The next one will be held in Jan 2010 and every alternate (odd) month thenafter.

I saw several members from the Green Culture Singapore discussion forum putting up stalls to sell their plants. TALOS was there with his range of begonias and carnivorous plants and greenhorn sold his collection of airplants. A few others formed groups to sell collector’s orchids and a multitude of plants, cuttings and seedlings from their gardens. The youngest participant for the bazaar was an enterprising 12-year-old boy named Bram Lim, who roped in his little brothers to peddle his home-grown plants. Talk about a bright green future (see picture above)!

Other activities for the day included the “Christmas in a Bottle” terrarium workshop and a talk on “How to Grow Your Own Culinary Herbs” conducted by myself, attendance was overwhelming despite the downpour. The celebration would not have been complete without Santa Claus, who came by to extend his greetings to all who were at HortPark that day.

The last Root Awakening column for the Year 2009 appeared on 19 Dec 2009′s edition of Straits Times Life! As usual, answers to three gardening questions were provided.

The first question asked why the base (probably pseudobulbs) of leaves of an orchid started to shrivel after it was located in a windy growing area. It is likely that the orchid plant is suffering from moisture stress due to exposure to excessive wind. One can try to relocate the plant to a less windy area or provide some protection by putting up a barrier to wind by growing them amongst some plants. Consider adding a little sphagnum moss around the root zone to help retain some moisture. It may be necessary to increase the frequency of watering too.

The second question asked why the laying of eggs by butterfly causes leaves to rot or dry up… My answer given was that the laying of eggs by butterflies and moths is not known to cause plant leaves to dry or rot. The problem probably lies in the fact of overfertilisation. Always remember to adhere to the manufacturer’s instructions in applying fertilizers, even if they are organic in origin. Too frequent applications as well as excessive amounts of fertilizers can ‘burn’ plants and cause damage similar to what you have observed.

The last question queried what are the creepers such as the morning glory vine that can be grown in a room. It is important to note that two hours of direct sunshine received in a room is definitely not sufficient to grow most sun-loving plants which include the morning glory vine. These plants need at least 6 hours of direct sunshine in order to thrive and flower.

If there is at least 4 hours of filtered sunshine, you may want to consider growing foliage houseplants with a vine-like growth habit such as the money plant, heart-leafed philodendron (Philodendron scandens ssp. oxycardium) and variegated cupid peperomia (Peperomia scandens ‘Variegata’). The wax flower (Hoya) is another plant to consider that produces attractive clusters of fragrant flowers.  Another relative of the wax flower you can consider growing is the ant plant (Dischidia pectinoides). This vine produces small red flowers accompanied by curious, balloon-like modified leaves.

The abovementioned plants can be purchased from most good nurseries in Singapore, such as World Farm, Far East Flora and Pioneer Landscape.

 The visitor to HortPark’s Lifestyle Corner this December would have noticed spices are used to make alternative  ornaments for the Christmas festive season. Instead of buying ready-made ones from commercial stores, some of us may want to take this opportunity to get everyone at home or in the office to come together to make some unique decorative items. You can also make use of this opportunity to teach your friends and kids where these spices come from and how they are used in flavouring food!

Spicy Christmas trees for the dinner table – all you need to do is to use hot silicone glue and stick various spices of your choice onto polystyrene cones. Seen here are ‘trees’ made from dried rose buds, cloves, cassia sticks, dried bay leaves, nutmeg and chillis!

If you have any faded baubles left over from previous years that are not nice enough for this year’s trees, do not throw them away! Reduce waste and turn them into new ornaments by dressing them up with spices! Shown above is an example of a bauble given a new lease of life after it has put on a new coat made up of star anise!

Another type of hanging ornament for the Christmas tree can be made from just a combination of spices. Shown above is a simple bundle of cassia sticks adorned with star anise and bay leaves which is strung with a golden string so that it can be hung up.

When making Christmas ornaments from spices, it is important to let your creative juices flow. Mix and match various spices to get the desired effect. Cassia sticks are very fragrant. Star anises with their star shape are great for the Christmas season. Dried chillis help to add a burst of red colour. Include also some dried bay leaves for the light green colour. Cloves are good for sticking into polystyrene cones and balls.

Besides looking great and unique, ornaments made from spices exude a delightful fragrance when they are made and displayed immediately. This is especially welcomed if you are using an artificial Christmas tree. These ornaments will last and in the tropics, store them in a air-tight bag with some silicon gel included to help absorb excess humidity after they are taken down after Christmas.

Besides being involved in decoration work for the Wedding Fair at HortPark that was held last Saturday, one of my team members, Pearl Ho, also conducted a floral arrangement talk cum demo session entitled ‘Bridal Bouquet Demonstration’.  Pearl introduced to her audience the diversity of flowers, foliages and various arrangement styles that can be used on one’s special day. She also taught all who were present on the importance of colour scheme.

In the beginning of her talk, Pearl presented a couple of traditional hand flower bouquets that are popular wedding must-haves. She also introduced a range of innovative, ‘green-themed’ ones which are created using potted plants such as Pilea ‘Moon Valley’ (noted for its textured leaves), variegated and all-green Ficus pumila, variegated Dischidia species and Episcia ‘Malaysian Gem’. These plants definitely last longer and are easier to maintain traditional bouquets made from cut flowers!

If your wedding reception has long tables, consider using floral displays with plants incorporated in them for a more lasting and unique arrangement. Shown here is a naturalistic display using a species of club moss for its interesting-looking foliage, Selaginella kraussiana ‘Brownii’,  which forms low, small clumps of whorled mounded leaves. Plants are potted up in small thumb pots which can serve as unconventional take-away souveniors for your guests.

Another table display, suitable for traditional round tables encountered in most receptions, is made up of orchids. Spider orchid flowers (Arachnis cultivar), shown in the example above, are also more-lasting flowers compared to many other imported flower species. They also lend a more tropical feel to the atmosphere. Foliage from the aparagus fern is used as a filler, which is also a durable floral material.

Shown above is a hanging arrangement created using spider orchids. Long-lasting, finely divided leaves from a common houseplant, the Ming Aralia (Polysicias fruticosa), are used as a filler in this fine example.

In line with a garden wedding in HortPark, Pearl transformed upturned coconut coir pots into wedding bells for a hanging arrangement which can be used to decorate a chair. These pots are very afforable and are available for sale in most plant nurseries. They are the tropical version of peat pots that are usually used to start new plants and then planted together in a final growing spot, which it will gradually degrade.

Lastly, do not despair if you missed this talk and demonstration! Pearl will be conducting similar workshops for registered groups in HortPark in 2010!

My team was involved in some decoration work for the Wedding Fair that took place in HortPark on last Saturday. This time, we helped to dress up a signboard (located at the Multi Purpose Hall) that showcased HortPark as a garden wedding venue in Singapore.

There are two sides to this signboard and because HortPark is a gardening hub, we conceptualised a design that also incorporated some gardening elements in it. A lush grouping of plants flanked both sides of the signboard depicted a garden scene. Airplant species such as Tillandsia xerographica and T. usneoides were used in the decoration as well. The frequent visitor to HortPark would have noticed the clumps of T. usneoides, commonly called Spanish moss, hanging from a rain tree planted in the Silver Garden, which is a popular photographic spot with wedding couples.

We quietly put two terrariums in this display as the terrarium workshop in HortPark has been a very popular gardening activity with visitors. Couples planning to tie the knot can also consider making their own terrariums and watch their love grow. They make ideal gifts for your guests who are invited to your wedding reception. Two spherical cages containing nerve plants is one idea we came up with that can be used in a decorative display in a gardening wedding.

One would have also noticed the use of the sweetheart hoya (Hoya kerrii) in this decoration work. It is one plant that symbolises love due to its attractive, heart-shaped leaves. It is a fuss-free and easy-to-grow plant that is available for sale planted in snail shells which is another ideal gift idea for your guests.

On the other side of the signboard, we added an assortment of fittonias presented in an array of dish gardens to confer some vibrant colour to the overall display via their colourful foliage. Flowers are often used for various purposes in weddings and to promote a green wedding concept, we hope to promote the use of plants as environmentally-friendly alternatives for consideration by green-minded wedding couples on their special day.

 The second instalment of the Root Awakening column for December 2009 was published today. The first question from a Straits Times Life! reader was about how festive citruses can be made to bear fruit while they are still small and seemingly young. Most of such plants are generally grown on a grafted rootstock. This rootstock is usually a vigorous citrus plant such as lemon and shoots from mature trees that are already flowering and fruiting are taken and then grafted to this rootstock.

The second question was similar to previous questions that have been published. It was about why the inflorescences of one’s orchid plant tend to turn brown and then die away. The problem is likely to be caused by excessive heat and moisture stress. Adding a little sphagnum moss around the root zone to help retain some moisture. It may be necessary to increase the frequency of watering too. Do also try to relocate the affected plant to a less windy area or provide some protection by putting up a barrier to wind by growing them amongst some plants. Check for spider mite and thrips infestations as well.

The last question dealt with the small, cottony insects that appear on a custard apple plant. The pests seen are likely to be mealy bugs. To eradicate these pests, one can spray infested plants using white summer oil or neem oil. Make sure every part of the plant is covered thoroughly, including the leaf undersides as well as any spaces between leaves. There is also a need to repeat application of the pesticide several times to ensure all progeny that hatch from eggs laid earlier are also eradicated. Check surrounding plants for any signs of infestations as well. Pests from these plants can migrate over at times. They should be sprayed as well if there is any signs of infestation.