Root Awakening: Asparagus fern needs sunlight to thrive

Asparagus fern needs sunlight to thrive.
Asparagus fern needs sunlight to thrive.PHOTO: CHIO POH LENG
Red Flame grows mostly as a weed.
Red Flame grows mostly as a weed.PHOTO: NICK CHOW K.T.
Sawtooth coriander grows easily in Singapore.
Sawtooth coriander grows easily in Singapore.PHOTO: TANG MUN YIN
Animals depend on mistletoe plant for food.
Animals depend on mistletoe plant for food.PHOTO: LOOK BOON GEE
Bleeding Heart Vine best grown in semi-shaded conditions outdoors.
Bleeding Heart Vine best grown in semi-shaded conditions outdoors.PHOTO: SIMON CHAN

Asparagus fern needs sunlight to thrive

This plant was green but turned brown. I have stopped watering it and have put it in the shade after noticing the change of colour. Is the plant dead? What is its name?

Chio Poh Leng

The dried plant in your photo is commonly called the asparagus fern.

Its botanical name is Asparagus setaceus and it is not a true fern. In fact, it is a relative of the edible asparagus, whose botanical name is Asparagus officinalis. It is commonly sold as a potted houseplant and its cut foliage is used in floristry.

From the photo, the plant is totally dried and will not recover. It is a plant which requires sunlight to grow and should be kept in a location with filtered sunlight for at least six hours daily.

The lack of light will cause the foliage to drop. The soil should be kept moist at all times and not allowed to dry out totally.

The plant grows as a climber and will need support for its stems to climb on.

There are spines on its more mature stems, so exercise care when handling the plant.


Red Flame grows mostly as a weed

Can you identify this plant which can be found almost everywhere in Singapore? It has a purple flower and deep green leaves.

Nick Chow K.T.

The plant is commonly known as the Red Flame and its botanical name is Strobilanthes reptans.

It grows in Singapore mostly as a weed - in sunny and shady spots - and can be seen in colonies in grass turfs and in between the concrete slabs at carparks.

Even a weed like this plant has an ecological role in Singapore's urban landscape - its leaves are food for caterpillars of the Chocolate Pansy butterfly.


Sawtooth coriander grows easily in Singapore

I was told this plant is celery. What is its name and what kind of plant is it?

Tang Mun Yin

The plant is commonly called the sawtooth coriander and its botanical name is Eryngium foetidum.

It belongs to the same plant family as the celery and common coriander, whose botanical name is Coriandrum sativum.

The common name of this plant is likely derived from the appearance of its leaf's edge, which is serrated like the edge of a saw.

The fresh leaves exude a pungent odour reminiscent of the common coriander. As such, a small quantity of finely chopped leaves can be used as a substitute.

This herb is used extensively as a culinary herb in Thailand and Vietnam and is easier to grow than the common coriander under Singapore's tropical conditions.


Animals depend on mistletoe plant for food

I found this interesting plant growing on the trunk of my kaffir lime tree. What plant is it and will it harm the host?

Look Boon Gee

Your kaffir lime plant is being parasitised by a mistletoe plant. The latter attaches itself onto its host via a specialised structure called the haustorium, which penetrates the host's stem/branch to draw water and nutrients needed for its growth.

The mistletoe plant has chlorophyll in its leaves and can photosynthesise to make its own sugars.

A large kaffir lime plant may be able to support the growth of the mistletoe plant. However, a large mistletoe plant may weaken the host and can cause its branches to break due to its weight.

In the latter case, you may want to prune the mistletoe plant to manage its size or remove it entirely, including the haustorium, to ensure the health of your kaffir lime is not compromised.

The mistletoe plant has an important role to play in Singapore's urban ecosystem as a wide range of animals feed on its leaves, shoots, fruit, flowers and nectar.


Bleeding Heart Vine best grown in semi-shaded conditions outdoors

Can you identify this flowering plant? It was dried up and I thought it had withered. Then, a week ago, it started to bloom with lovely flowers.

Simon Chan

The plant is botanically known as Clerodendrum thomsoniae and its common names include Bleeding Heart Vine. The plant's flowers are red and emerge from the rather prominent, white, bloated, heart-shaped calyx. The colour contrast is exceptionally eye-catching.

The plant grows naturally as a climbing vine, but can be pruned to grow as a shrub. It is best grown under semi-shaded conditions outdoors in well-drained but moisture-retentive soil.

There is a variegated version of this plant, which has attractive leaves edged with white and is sometimes sold in local nurseries.

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

• Have a gardening query? E-mail it with clear, high-resolution pictures of at least 1MB, if any, and your full name to stlife@sph.com.sg. We reserve the right to edit and reject questions.

A version of this article appeared in the print edition of The Straits Times on August 31, 2019, with the headline 'Root Awakening'. Print Edition | Subscribe