Bread Flower climber's fragrant blooms used in potpourri
I would like to know the name of this plant. Its white flowers have a soothing fragrance.
The plant is botanically known as Vallaris glabra. It is a large climber with flowers that produce a scent similar to that of the fragrant pandan. Its common names include Bread Flower and Bunga Kesidang.
The bloom is the state flower of Malacca and, in the past, Malay women would tie their hair in a bun and decorate it with the flowers.
They are often used in a special potpourri called "bunga rampai" for Malay weddings.
This plant is a delightful one to have if you have an outdoor garden with a sturdy pergola or trellis which it can climb on. It thrives in well-drained soils with full sunlight exposure.
Laksa plant stressed from rooting
I planted a laksa plant from a stem cutting. The ends of the leaves were already brown. The plant has grown, but the ends of most of its leaves are brown. I water it twice a day and it gets some sunlight. Is the problem due to underwatering or overwatering? Also, I have been reading your Root Awakening column. Where can I find past columns?
From the picture, the new growth appears normal. Hence the browning of leaf tips appears to be a response to stress that occurs during the stem-cutting rooting process.
The laksa plant (Persicaria hydropiper) is a water-loving plant. When growing stem cuttings, the environment should be kept cool, moist and humid.
Environmental stress, in the form of heat (from those few hours of sunlight) and lack of moisture, experienced during the rooting stage, can lead to browning leaf tips.
To prevent this from happening, when new stem cuttings are being propagated, it is advisable to root them in a moist but well-drained media. They should be placed in a cool location with some filtered sunlight.
There may be a need to keep the cuttings under a transparent, perforated cover to conserve moisture. The growing environment should not be overly shady as the lack of light and overly wet conditions can lead to disease.
Some people root the cuttings in water. When roots start to grow, they can be moved into soil.
You can read past Root Awakening columns at the National Library's online newspaper archives. Go to eresources.nlb.gov.sg/newspapers.
Broad mites infesting chilli plants
I grew these capsicum plants from seeds for more than six months. In the last two weeks, they seem to be in poor health. I water them every day and place them in the corridor, where they get a good amount of sunlight. What is happening to the plants and can they be saved?
Your chilli plants are infested by a microscopic pest called the broad mite. Broad-mite feeding causes leaf edges to curl downwards and become brittle and puckered. The undersides of leaves turna shiny, bronzed colour and the growing point often dies.
The only effective, organic means of management is to apply a dilute solution of sulphur soap on affected plants.
The solution can be made by dissolving a teaspoon of sulphur soap flakes - grated from a soap bar meant for skin issues - in a small amount of hot water. This is then topped up to 1 litre with tap water.
The infestation on the plants appears to be quite serious and can be difficult to treat.
You may have to apply the sulphur soap solution every three to four days to suppress the broad mite population.
Calla lily thrives in a cooler climate
I bought this lily plant in December last year. The colour of the petals never turned white, but remained green throughout. Now, the tips of the flowers have started to yellow. What can I do to make the plant grow better?
Sim Poh Thien
The plant is the Calla lily (the botanical name is Zantedeschia hybrid).
The so-called petal on the inflorescence is actually a modified leaf called a bract and is characteristic of plants from the arum family (Araceae).
When the inflorescence ages, it is normal for the bract to turn green and eventually brown as it deteriorates over time.
You can prune spent inflorescences.
What you have is likely a deciduous complex hybrid of a different South African species.
In warm areas, these plants have an underground rootstock and are often grown at higher altitudes. The temperature at night needs to be much cooler than in the day and the plants generally require a rest period to thrive.
As such, it may be a difficult plant to grow well in tropical Singapore and is best treated as a temporary display plant here.
Guiana chestnut is a festive plant
I spotted this small tree at Pasir Ris Park. Could this be guava or avocado?
The fruit is produced by a tree that is botanically called Pachira aquatica. Its common names include Malabar chestnut, Guiana chestnut and Provision tree.
Saplings of this species, with long pliable stems braided together, are often sold as Chinese New Year festive plants for display. They can also be found at festive marketplaces.
•Answers by Dr Wilson Wong, a certified practising horticulturist and founder of Green Culture Singapore (www.green culturesg.com). He is also an NParks-certified park manager.
•Have a gardening query? E-mail it with clear, high-resolution pictures of at least 1MB, if any, and your full name to firstname.lastname@example.org