Monthly Archives: March 2009

Rare sight – Indian Borage flowering!

Posted on March 9, 2009 | 2 Comments

I pounced upon something that I have never witnessed before. I have grown the Indian borage plant (Plectranthus amboinicus), both the all green version as well as the variegated one, but I have never seen its flower with my own eyes before. My observation was also echoed in PROSEA’s entry on the Plectranthus – Plectranthus amboinicus rarely flowers in Malesia. It is a popular herb grown by many Singaporeans for the use as a treatment for coughs and sore throats.

I visited Oh Chin Huat Hydroponic Farm over the weekend and at their medicinal herb garden, I caught a glimspe of the flowers borne by the Indian borage. Numerous light blue flowers were borne on a terminal spike. Individual flowers were small and has a distinct lip with four yellow spots. They are reminiscent of those produced by the so-called colourful foliage coleus plant which has now been reclassified under the new genus Solenostemon.  

This brings us to the three closely related genera in the mint family, Lamiaceae – Plectranthus, Coleus and Solenostemon. At present, there is still much disagreement about generic delimitation in these three genera.

In my favourite reference PROSEA, under the entry for Plectranthus, it was stated that, strictly speaking, Coleus is often considered as distinct from Plectranthus, on the basis of the fused bases of the calyx filaments. However, this is a variable and unreliable character. It is not unusual to see Coleus is still considered as a synonym of Plectranthus. In some herb books, one will see the Indian borage known as Coleus amboinicus.

Those colourful foliage plants now classified under the genus Solenostemon have calyx segments that are about equal whereas Plectranthus species have a a distinctly 2-lipped calyx.

Sounds confusing, isn’t it? Frankly, I have taken the above distinctions for granted as a gardener for a long time as I have never went into looking at the plants closely. It is perhaps time that I go pick some flowers borne by these three genera so as to be able to take a closer look at them.

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Posted in Herbs

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Root Awakening (7 Mar 09)

Posted on March 7, 2009 | Leave a comment

The first instalment of the Root Awakening column for the month of March 09 was published today and three questions from readers were answered. The announcement about my upcoming talk about plants belonging to the Zingiberales order to be conducted at the Singapore Botanic Gardens next Saturday was also put up.

The first question was about the Venus fly trap and whether should the plant be allowed to flower. One may be curious about how the flower of this carnivorous plant looks like but has be cautioned that if the plant is allowed to flower, it may die from the process. This has been experienced by some of my friends who are carnivorous plant growers from the Green Culture Singapore discussion forum.

The second question was about growing sunflowers. From my experience, it can be very difficult to grow these cheerful flowering annuals in a high-rise apartment where direct sunshine is not often available for longer than 4 hours daily. Next, plants are best grown in fertile soil and fed generously to keep up with their growth. I have grown sunflowers before and they do best outdoors in full sun and planted in the ground, well fertilised.

The last question dealt with problems faced with growing basil. Basil plants are prone to pest attacks and the two most common pests I have encountered before were aphids and spidermites. These two are most easily eradicated only when the infestation is spotted early. Unfortunately, plants succumb to heavy infestations quite easily and quickly. Basils also need to grown in well-drained soil and in direct sunshine. Although they need to be well watered, they do not like to experience constant wet feet. If the plants are grown in such conditions, they tend to rot and that happens in the zone nearest to the ground.

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Posted in Root Awakening in ST Life!

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Green Culture Singapore Feature Articles (Feb 09)

Posted on March 5, 2009 | 2 Comments

I admit that I have been way too late to have put up February’s Green Culture Singapore gardening feature articles.  Work has been hectic lately but I have managed to upload two gardening feature articles for leisure reading by my members at the Green Culture Singapore discussion forum. It’s better to be late than never!

The two feature articles focussed on hoyas this time around. The first article was contributed by Crocus Sativus which was an interview with  Anders Wennstrom, a co-author of the book entitled “The Genus Hoya”. I have obtained a copy via the help of a good friend and I found it extremely informative!

An Interview with Anders Wennstrom

Hoya enthusiasts would have heard about the publication of a new book entitled “The Genus Hoya” that was written on this fascinating group of plants. Read this feature article that was contributed by Crocus Sativus which is an insightful interview with Anders Wennstrom, who is a co-author of the book. This interview was reproduced with permission from the Singapore Gardening Society.

URL – http://www.greenculturesg.com/articles/feb09/feb09_wennstromintervw.pdf

 

The second article was a joint effort between my fellow colleague at HortPark, Jin Hong and myself. This feature article can likened to be a follow-up of the gardening talk that was held on this year’s Valentine’s Day in HortPark. It serves to introduce to the public the heart-shaped leaves of the sweet heart hoya (Hoya kerrii) which can become popular gifts for one’s partner on Valentine’s Day. In it, there is a series of steps which can be easily followed by the layman to teach one how to paint these heart-shaped leaves, as well as, cultivation information that is applicable to the sweet heart hoya and other Hoya species.

Grow Your First Hoya Plant with Love

Although roses are traditionally associated with Valentines’ Day, there are also other plants that can be used to convey your feelings to your loved ones. For those of you who have received a heart-shaped leaf that is potted up and adorned with sweet nothings and motives of hearts and other love symbols, the leaf you have gotten as a gift actually came from the sweetheart hoya plant. Read this feature article to know more about the sweet heart hoya and learn how to grow it. This article also contains basic cultivation information that is relevant to most other Hoya species.

URL – http://www.greenculturesg.com/articles/feb09/feb09_hoyakerrii.pdf

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Posted in Contributed Articles, GCS Feature Articles

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Hoya multiflora – The Shooting Stars Hoya

Posted on March 3, 2009 | 1 Comment

I received a Hoya multiflora as a gift after attending National Parks Board’s (NParks) Streetscape Strategic Planning Exercise that was conducted at Botany Center yesterday. The plant was grown inside a large snail shell that was attached at the end of a metal hanger and this makes it a nifty plant gift that will delight anyone who receives it. It can potentially push one to find out more about its growing needs, get one to love plants and make them fall for the gardening hobby!

Native to this part of the world, Hoya multiflora is commonly called “Shooting Stars” due to the unique appearance of the flowers. Similar to the flowers of other Hoya species, the flowers of this particular species have five petals and hence look like a star. But the ones produced by Hoya multiflora are different from the rest as they are reflexed backwards and this feature makes its flower look like shooting stars when viewed sideways.

The plant I got was grown using a minimal amount of substrate. But resist the temptation to repot the plant as hoyas are best grown potbound and as overpotting poses a chance that the plant’s roots are constantly kept wet. Overwatering or prolonged wet feet can cause the plant\’s roots and stems to rot away! Hoyas, like most other epiphytic plants, need to be watered regularly but the roots must be allowed to dry out a little before the next round of watering. Grow this plant in an area where it can get filtered sunshine for at least 4 to 6 hours daily.

This Hoya species adopts a shrub-like growth habit and does not really climb up supports. Leaves are large and dark green in colour. Its flowers are borne on an umbel and emit a strong fragrance. From the second picture shown above, the flowers can be seen to be producing generous amounts of clear nectar that appear as large droplets hanging from each flower. These sweet droplets are meant to attract pollinators to the flowers.

As stated in the new Hoya book entitled “The Genus Hoya“, written by Anders Wennstrom and Katarina Stenman, Hoya multiflora may be reclassified into a different but related genus called Centrostemma, due to the presence of features that make it differ from other Hoya species.

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Posted in Flowering plants, Houseplants, Tropical ornamentals

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Andrew’s Article on the Mondo Grass

Posted on March 1, 2009 | 1 Comment

Andrew wrote yet another insightful article on a plant that I have overlooked for a long time. He wrote on the Mondo grass which is a grassy plant that is botanically known as Ophiopogon jaburan and a member of the lily family, Liliaceae.

The Mondo grass is a common landscape candidate due to its ability to establish quickly and easily, valued for its drought tolerance and is disease- and pest-free. Compared to many other grass-like plants, it does not spread as fast and hence they pose less of a worry to become weedy.

In the garden, it should be grown in a semi-shaded location although it can be adapted to grow in full sun. It should be planted in moist and well-drained soil. The Mondo grass does not tolerate waterlogged conditions. As mentioned by Andrew, this plant is suitable for container culture, hence apartment gardeners with a well-lit spot at home should consider growing the Mondo grass if one desires a grassy plant.

The all green variety can be found on sale in nurseries and seen being planted in some outdoor landscaped gardens. Pictured in Andrew’s article was the more attractive, variegated version of the Mondo grass, O. jaburan ‘Variegata’, which can be used as in the garden as an accent plant to add contrast and color.

Another Ophiopogon species that is well liked by some Singaporeans is the Kyoto grass, which is botanically known as O. japonicus ‘Kyoto Dwarf’. As its cultivar name suggests, this variety is a miniaturised version of the normal mondo grass-like plant. It forms compact tufts consisting of dark green leaves less than 8 cm long. It is a slow-grower and spreads slowly. One has to plant a lot of this plant in a patch of land to ensure it looks ‘filled’!

Click on this link which will bring you to a comprehensive pdf article written about the Mondo grass and its relatives that was published online by the College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa.

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Posted in Newspaper features, Tropical ornamentals

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