Succulents need gritty growing media and direct sunlight

My succulent keeps dying. I have changed the watering pattern and placed it in a well-lit spot, but to no avail. What is wrong?

Rithanya K.S.

Depending on the succulent species, your plant needs at least four hours a day of direct sunlight. Succulents are sun-loving plants and the heat from the sun helps to dry their growing media, thereby preventing disease and rot due to wet feet.

As it is often rainy in Singapore, it is better to grow such plants in a sheltered spot so the root zone does not get wet. Try growing your plant in a gritty mix of pumice, lava sand and perlite. Such a porous mix will promote drainage and aeration.

In the picture, the growing mix appears to be based on organic matter such as cocopeat and peat moss. This is a water-retentive mix that is generally unsuitable for growing succulents in the tropics.

Nappy tree is native to Singapore

I found this plant in my garden. What is it and should I keep it?

Andrew Chan

The plant shown in the picture is likely the Nappy Tree (Claoxylon indicum). It is native to Singapore and can be found growing in sunny spots in secondary forest edges or open areas. Given time, it will grow into a tree.

The location shown in the picture may not be a good site for the plant. As it grows, its roots may damage the area. You can try to transplant it by digging a large root ball and moving it to an area where there is more space to grow. After that, water the plant well and place a cloth above its growth area to help it recuperate in the shade.

Pineapple stump's offsets can be removed and planted

I planted a pineapple in a large pot two years ago and recently harvested a big fruit which was sweet and fragrant. Will the same plant continue to bear fruit or do I have to replant it?

Lee Chee Chee Thomas

Once a pineapple plant has fruited, it will die. However, the crown will produce offsets, also called suckers, between the leaves which will take over and grow. These can be removed once they are large enough and potted separately.

Once they have produced roots and settled in their new location, they can be planted in larger pots or in the ground with well-drained soil.

Depending on the variety, new plants can take at least two years before they start to flower and fruit.

Plant leaves infested with bagworms

What creatures are on the leaves of my plant and are they harmful?

Khor Kok Wah

Your plant appears to have a bagworm infestation. Look under the leaves and you may see cones. Caterpillars of certain moth species construct a protective case made from leaves and feed on the underside of these leaves, eventually creating holes in each leaf. In severe cases, the leaves develop numerous holes.

Bagworms can be managed by spraying dipel, a microbial-based pesticide which is specific to caterpillars. It needs to be applied on all parts of the plant with thorough coverage.

Plants are Spearmint, Dogfennel and Wild Pepper

What are these plants? Are they edible?

Roger Lim

Plant A appears to be spearmint (Mentha spicata), which is edible and can be used to flavour beverages and made into mint jelly or sauce. Its lanky appearance is an indication that it is not getting enough sunlight. It thrives best when exposed to at least four hours a day of direct sunlight. Keep it moist and do not let it dry out.

Plant B may be dogfennel (Eupatorium capillifolium). It is commonly confused with the dill plant. It is not edible as it reportedly contains alkaloids which may affect liver function.

Plant C seems to be the wild pepper (Piper sarmentosum). It is native to Singapore and grows well under filtered sunlight. The plant has medicinal properties and is used as an ingredient in nasi ulam.

• 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.