Root Awakening: Violet Ixora a flowering shrub, wild pepper's leaves used as food wrap

The violet ixora (left) and the wild pepper plant.
The violet ixora (left) and the wild pepper plant.PHOTOS: GERALD OH, CHONG KHIONG LIN

Flowering shrub known for shade tolerance

What is the name of this plant in the Botanic Gardens? It seems to be able to flower despite growing in the shade of larger trees.

Gerald Oh

The plant is botanically known as Pseuderanthemum andersonii. Its common names include Violet Ixora, Blue Twilight and Florida Twilight. It is a flowering plant known for its shade tolerance, but grows best in a location where it can get six hours of filtered sunlight a day. A lack of light will produce weak, lanky plants that do not flower well.

Leaves of wild pepper used as food wrap and in salads

What is this plant? I have been told its leaves are edible.

Chong Khiong Lin

The plant is commonly called wild pepper or daun kaduk and its botanical name is Piper sarmentosum. It is a native plant of Singapore and grows well under semi-shaded conditions. As such, it is commonly planted as groundcover in outdoor landscapes.

Its leaves have a spicy flavour and can be used to wrap snacks. The sliced leaves are also added to nasi ulam, a Malay herb rice salad.

Try growing it in your home or community garden for culinary uses, but note that it is an offence to harvest from public green spaces without permission.

Ruby Leaf Alternanthera grown as an ornamental

The Ruby Leaf Alternanthera is usually grown in gardens as an ornamental plant, where its red leaves add colour to a largely green landscape. PHOTO: TEA ANN LEE

I received this plant as a gift and would like to know its name and uses. Can it be found in the local markets or nurseries?

Tea Ann Lee

The plant is botanically known as Alternanthera dentata and its common name is the Ruby Leaf Alternanthera. In Singapore, it is usually grown in gardens as an ornamental plant, where its red leaves add colour to a largely green landscape.

It grows fast and is easily propagated from stem cuttings. It is sometimes sold in local nurseries. It can be eaten and is used in traditional medicine.

Rose bushes damaged by thrips

The rose plants have been infested with thrips, which are tiny rasping pests that scrape and damage plant tissue surfaces. PHOTO: MALATHI SITARAM

My rose bushes are developing stunted, curling leaves with brownish stains. The stems also seem to have reddish stains. The leaves look unhealthy. What can I do about this?

Malathi Sitaram

Your rose plants are infested with thrips, which are tiny rasping pests that scrape and damage plant tissue surfaces.

During the hot season, plants are stressed and more susceptible to infestations. Shade plants slightly and water deeply to mitigate this.

Thrips are difficult to manage, but can be controlled using pesticides such as spinosad and fipronil. Note that these can be costly and need to be rotated with other pesticides to reduce the chance of the pests developing a resistance.

Protect gooseberry plant from the elements

The gooseberry plant could have been damaged by the harsh rooftop environment, or by rain. PHOTO: JENNIFER WONG

We planted gooseberry in our office's rooftop garden. The plant sprouts, blooms and fruits, but the leaves wither. It receives sun, rain and wind. We tried neem oil and sulphur lime, but nothing seems to work.

Jennifer Wong

The exact cause of the issue is difficult to discern from the picture. Note that a rooftop environment is harsh. It is hot and dry, and frequent winds may dry the plant out. The plant can also be damaged by rain.

You may want to put up a clear plastic rain shelter to protect the plant. This can reduce tissue damage by heavy rain as well as possible secondary infections. Also, drape a light cloth over the shelter to shade the plant in hot weather.

  • Answers by Dr Wilson Wong, an NParks-certified practising horticulturist, parks manager and ISA-certified arborist. He is the founder of Green Culture Singapore and an adjunct assistant professor (Food Science & Technology) at the National University of Singapore.
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