Root Awakening

Jambu Air Mawar, which is also known as the Java Apple.
Jambu Air Mawar, which is also known as the Java Apple.PHOTOS: DOLLY QUAH, EDWARD OW, JUPITER LAY, TJIN TJIN TJOA
Lacy Lady Aralia or Zodia.
Lacy Lady Aralia or Zodia.PHOTOS: DOLLY QUAH, EDWARD OW, JUPITER LAY, TJIN TJIN TJOA
Yellow Cane Palm (botanical name: Dypsis lutescens).
Yellow Cane Palm (botanical name: Dypsis lutescens).PHOTOS: DOLLY QUAH, EDWARD OW, JUPITER LAY, TJIN TJIN TJOA
Caricature Plant
Caricature PlantPHOTOS: DOLLY QUAH, EDWARD OW, JUPITER LAY, TJIN TJIN TJOA

Fruit of Java Apple are edible

This plant is grown on an open Housing Board ground in a big pot. It bears a lot of fruit. Usually, the red version is easily available, but not the green ones. Is this fruit edible?

Dolly Quah

From the features of the leaf and fruit, the tree is likely the Jambu Air Mawar, which is also known as the Java Apple. Its botanical name is Syzygium samarangense and it is a member of the guava family, Myrtaceae.

Its fruit can be light red, greenish-white or cream-coloured and are edible.


Lacy Lady Aralia shrub best in sunny spot outdoors

What is this plant? My mum's cats love to nibble on the leaves.

Tjin Tjin Tjoa

The shrub is called the Lacy Lady Aralia or Zodia. Its botanical name is Euodia suaveolens and its leaves emit an odour.

Although it can tolerate some shade, this plant is best grown in a sunny spot outdoors, where the leaves can take on a bright yellow-green colour. The site should also be well-drained.


Palm may have nutrient deficiency

Some of the leaves of my plant have wave-like patterns and, after a while, they become torn. What is causing this?

Jupiter Lay

The plant is likely a species of palm. You may want to verify if it is the Yellow Cane Palm (botanical name: Dypsis lutescens).

The distortion of the young fronds could possibly indicate a deficiency in boron - a plant nutrient - a common issue in palms.

There may be insufficient boron in the growing media, where the supply of the nutrient is exhausted due to severe leaching or lack of fertiliser.

Other common causes include dry soil and high soil pH levels. In the case of the latter, the soil pH level is in the alkaline range, where boron is locked up and not available for absorption by the plant.

For now, you may want to check the soil pH level and ensure it is in the optimal range for the growth of your palm. You can adjust the soil pH level, but changes will take time.

If the pH level is in the optimal range, ensure that the plant's roots do not dry out too often and feed the plant with a water-soluble fertiliser that contains boron.


Caricature Plant thrives with adequate sunlight

How do I grow this plant? Large brown patches appear on its leaves and enlarge quickly. What is the reason for this?

Edward Ow

The plant is commonly called the Caricature Plant. It is likely the cultivar called Roseum Variegatum of Graptophyllum pictum.

The issue may be due to fungal or bacterial disease. If only a few leaves are infected, you can cut and discard them to reduce the spread of the disease.

Make sure that your plant is grown under direct or filtered sunlight for at least four hours daily. Also, ensure that you do not injure the leaves as this will lead to wounds that are entry points for the disease.

• 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.

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A version of this article appeared in the print edition of The Straits Times on May 25, 2019, with the headline 'Root Awakening'. Print Edition | Subscribe