Root awakening

Blue Pussyleaf weed can help reduce soil erosion.
Blue Pussyleaf weed can help reduce soil erosion.PHOTOS: KOH SOH LING, LILY LIM, OEI KHOEN HWA, PECK LIN, TOM TAY
Bitterweed used to treat colds.
Bitterweed used to treat colds.
Cochineal Cactus has edible shoots.
Cochineal Cactus has edible shoots.
Burnt leaves due to fertiliser.
Burnt leaves due to fertiliser.
Leaves of Longevity Spinach believed to lower blood pressure.
Leaves of Longevity Spinach believed to lower blood pressure.

Blue Pussyleaf weed can help reduce soil erosion

What is this plant and is it edible?

Koh Soh Ling

This groundcover plant is commonly known as the Blue Pussyleaf. Its botanical name is Nelsonia canescens. As this weed often colonises shaded areas of a garden, it can be grown in low-light areas that need greenery or to reduce soil erosion. This inedible plant produces furry inflorescences.

Bitterweed used to treat colds

What is the name of this plant, which is known as yi yeng he in Hokkien?

I boil its dried leaves and drink the brew to dispel heatiness and get rid of a sore throat.

Peck Lin

The medicinal shrub is botanically known as Andrographis paniculata. Its common names include chuan xin lian, Bitterweed and King of Bitters.

Many people here use the plant to treat colds, sinusitis and other upper respiratory ailments. It grows best in moist, well-drained soil and should be placed in a location where it gets direct or filtered sunlight.

When growing conditions are ideal, this plant will self-sow its seeds in the surrounding area.

Cochineal Cactus has edible shoots

Is this cactus edible?

Lily Lim

The Opuntia cochenillifera is known by common names such as Cochineal Cactus and Nopalitos. The tender, young shoots can be pickled and put in a salad. This species is distinguished by its relatively thin stem segments and small leaves that appear with new growth.

Burnt leaves due to fertiliser?

My Episcia plant has luscious growth and is healthy, but produces very few flowers. I find it difficult to apply fertiliser to the soil around the roots because of the thick growth. The fertiliser I use seems to have burnt the leaves and left mushy spots. What fertiliser should I use?

Oei Khoen Hwa

I believe you use slow-release fertiliser pellets, which injure the plant. The mushy spots look like fertiliser burns. Cut these portions to prevent the spread of a secondary fungal or bacterial infection to the rest of the plant.

For plants that form a dense carpet such as your Episcia plant - it is also known as Flame Violet - it is best to use a water-soluble fertiliser where nutrient salts are dissolved in water and then fed to the plants.

Make a more diluted dose than what is recommended on the product's label to avoid burning the plants.

Leaves of Longevity Spinach believed to lower blood pressure

What is this plant and how do I care for it? I was told it is native to Taiwan, has detoxifying properties and can lower blood sugar levels.

Tom Tay

The botanical name of the plant is Gynura procumbens. It goes by common names such as jian feng wei, the Chinese hanyu pinyin word for Pointed Phoenix Tail; Longevity Spinach; Scrambling Gynura and Sambung Nyawa.

Its young leaves can be eaten raw or cooked. In Singapore, some Chinese believe that eating the leaves can lower blood pressure and reduce blood sugar levels.

This plant can be grown either under direct or filtered sunlight. The soil should be moist and well-drained. The plant can be propagated easily from stem-cuttings.

Snails and slugs like to attack this plant during the wet season, so take measures to stop these pests, especially if the plant is grown in an outdoor garden.

• Answers by Dr Wilson Wong, a certified practising horticulturist and founder of Green Culture Singapore ( 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

A version of this article appeared in the print edition of The Straits Times on September 16, 2017, with the headline 'Root awakening'. Subscribe