African Hosta is not edible

What is this plant? It was left behind by my late mother, who said the bulb is edible.

Patricia Ling

The plant is commonly known as Little White Soldiers or African Hosta and its botanical name is Drimiopsis maculata. It is not grown as an edible plant and should not be eaten. It is mainly cultivated as an ornamental species for its attractive leaves and growth habit.

Periwinkle is a toxic plant

What is this flower? Is it poisonous?

Quek Hock Chee

This plant is the Periwinkle (Catharanthus roseus), which is grown for both ornamental and medicinal purposes. All parts of the plant are toxic, so keep it out of the reach of children and pets.

Bamboo Orchid thrives under direct sunlight

My friend gave me this orchid plant two years ago. No flowers have bloomed and the leaves have turned yellow. What is wrong?

Lai Kwok Hong

This plant is commonly called the Bamboo Orchid (Arundina graminifolia). It thrives when grown outdoors in a well-drained site which gets at least six hours of direct sunlight a day. The lack of light could be a reason for the lack of flowers.

The yellow leaves could be due to a nutrient deficiency. Feed and water your plant regularly, and do not let it dry out too frequently.

Snake Plant may be rotting at the base

I have had this "tiger tails" indoor plant for about two years. Recently, the leaves have thinned and withered one by one. What is wrong?

Quah Tan Peng

The plant is a cultivar of Dracaena trifasciata, commonly known as the Mother-in-law's Tongue or Snake Plant.

If the yellow leaves are dry, then there is probably little cause for concern as older leaves die and are replaced by new ones.

However, if the leaves are mushy, check whether the plant has been overwatered. This plant does not tolerate wet feet, and its growing medium should be gritty and well-drained. It should be grown in a sunny spot and allowed to dry out slightly between each watering.

Be careful when potting the plant as the crown may rot if the plant is buried too deeply. Depending on the extent of the rot, the affected parts can be pruned and the wounds allowed to dry before replanting.

Queen of the Night's fruit are edible

My Queen of the Night (Epiphyllum) flowers frequently and recently bore two fruit. How do I tell when the fruit are ripe and are they edible?

Linda Tan

Although the Epiphyllum fruit is not usually eaten, fruit produced by cacti are edible. When ripe, the Epiphyllum fruit turns reddish-pink and its pulp is white when cut. It resembles - and tastes similar to - the white-fleshed dragonfruit (Selenicereus undatus).

• 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.
• 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.
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