Root Awakening: Withhold watering to help Amazon Lily flower

Plant produces scented white blooms

I bought this plant as a bulb a decade ago. I thought it was a foliage plant and noticed only recently that it has flowered. What is this plant and how can I get it to flower more?

Joseph Choo

This plant is the Amazon Lily (Urceolina × grandiflora) or Eucharis Lily. It produces clusters of scented white flowers and thrives in semi-shaded outdoor conditions. Alternatively, give it four hours a day of filtered sunlight in a high-rise setting.

This plant flowers under drought stress and when there is a drop in ambient temperatures. You can withhold watering to trigger flowering. The lower temperatures during the rainy season here may be another trigger.

Check root health of lemon tree

My lemon tree is shedding leaves. I use white oil on the branches to treat potential fungi and fertilise the plant fortnightly. What is wrong?

Chris Chan

Lemon trees exhibiting such issues could be having problems taking up water. In a moisture-stressed plant, older leaves turn yellow and fall off.

Is your plant being watered regularly? Do not let it dry out, as this can kill the fine root hairs that enable the plant to take up water. The plant will need time to recover and produce new roots.

Alternatively, the plant could be shedding leaves due to poor soil conditions. Do not grow this plant in heavy, clay-like soils, which can become compacted over time and make it difficult for water to pass through to reach the roots. This can result in poor root development and poor water drainage.

Check the soil and add amendments, if needed, such as good-quality organic compost. Ensure you do so without damaging the lemon tree’s roots. This can be a challenging process, so handle the plant with care.

Did the leaves fall after you applied white oil or other pesticides? When applied at the wrong time of day or in too high a dose, pesticide can damage leaves and cause them to fall. Always test a small amount on a part of the plant before applying on the rest of the plant, and do so during a cooler time of the day.

Also, white oil is primarily a pesticide and is not an effective fungicide.

Hand-pollinate soursop to ensure fruit production

My soursop tree is flowering but not fruiting. How can I get it to bear fruit?

Susan Chew

This could be due to the lack of natural pollinators in an urban environment. You will need to perform hand pollination to encourage fruit production.

Soursop flowers have both male and female reproductive organs, but have a protandrous flowering habit. So, the plant’s male floral parts shed pollen first before the female part becomes receptive.

You need to collect the pollen from the flower when it opens in the morning. Store it overnight in the refrigerator. The next day, after the stigma (a bulbous structure with a sticky surface in the centre of the flower) becomes receptive, dab some pollen on a small, fine paintbrush and apply this to the stigma.

Plant is the Queensland Bottle Tree

What is this plant and how do I care for it?

James Goh

This plant is commonly known as the Queensland Bottle Tree (Brachychiton rupestris). It is a slow-growing and drought-tolerant plant. Water it thoroughly and let it dry out before watering again. In hot and humid Singapore, ensure the plant is kept in a gritty and well-draining growing mix to ensure proper drainage and aeration.

It grows best when it gets at least four hours of direct sunlight a day in an apartment setting. Do not keep it in deep shade.