Common ailments / pests in homes in Singapore, and How to Resolve?

“I still don’t know who is the culprit of the mass killing of my plants!!” 

Ever found yourself feeling this frustration, and asking this question? 

New and experienced gardeners alike, are all susceptible to the plant ailments and garden pests. Some seem to have it better than others, but that is because they have been through some “pesty-times” that have taught them to handle (or rather prevent) pests and plant ailments more effectively. No worries though! With a couple of prevention techniques put in place, most will experience a significant decrease in the occurrences of plant ailments and pests issues.

Common Plant Ailments

1) Dried Out Plants

Unless one’s sole profession is to care for plants (and plants only), many are not accustomed to the regularity and consistency required for watering of their plants. As a result, irregularly watered plants can suffer very much from the drastic changes in soil moisture, water pressure exerted on the roots, etc. Humans and plants alike – the lack of water or drastic changes can draw life out of them. 

Dried up Curry Leaves
Dried up Apple Mint

With urban lifestyles, it can pose quite a challenge to make it a habit to remember to water the plants. Unfortunately, plants can’t bark, nor do they pounce on you like cats or dogs to remind you that you have forgotten to feed them water. 

However, the fortunate part and simple resolution for keeping your plants well-hydrated is to adopt some self-watering mechanisms! Thanks to designers who understand the sorrows of discarding or cleaning up a dried out plant, self-watering mechanisms such as self-drip bottles, self-water pots (typically pot attached to a water source, reservoir of water), or hydroponic systems are some effective set-ups that can save you and more importantly your plants!

Self Watering Pot Singapore
Self-Watering Pot

2) Root Rot

Ahhh.. this one, a common issue with new gardeners or experienced gardeners handling new types of plant varieties which they have never dealt much with before. 

The causes of root rotting can range from bacteria in the soil, pest-infection of the plant, pest-filled soil, to over-watering of the plant. Yes, underwatering is an issue, so can over-watering be!

Root Rot in Singapore Plants

Typical causes of infected soil (bateria, pest-filled with gnats or mites) can stem from improper composting of food scraps, or too much moisture in the soil caused by poor drained soil or simply over-watering. Unless properly broken down prior, fresh food scraps added to the soil typically attract pests due to its “sweetness” and remnant flavour. Also with high moisture content in fresh food scraps or from over-watering, these create a super moist environment making it a welcoming environment for pests or even mould development. With much bacterial and pest activity around the root area of the plant, it becomes very likely for the roots to begin rotting. With the roots continually soaked in a wet medium, they tend to mush up and rot as well. 

To resolve, first and foremost is to remove the plant and its roots from the infected soil. Secondly, if still salvageable, rinse off any mushed up slime around the root area and with a clean pair of scissors cut off excess roots that do not look firm and healthy. 

Next, to reduce bacteria and pest activity in the soil, consider pouring boiling water over the soil to kill bacteria and pests amongst the soil. Let the soil particles soak in the boiling water for at least 5 minutes, and the heat should do the job of eradication!

3) Yellowing and Falling Leaves

Yellowing leaves are a typical sign of micronutrient deficiency. Depending on the growing medium (type of soil or water) used, certain plant varieties will require more or less of a type of nutrient in order to grow healthily. A chart below kindly put together by gardening professionals ( highlights some typical yellowing conditions and their associated deficiencies:

Plant leaves colour meaning

The natural question after identifying the deficiency is then, how to appropriately compensate for the deficiency? 

A quick way to resolve would be to add nutrient/fertiliser solutions (i.e. N-P-K fertilizers, calcium-magnesium solutions) to balance out the deficiency. However, natural food waste such as dried and crushed egg shells can also be added and mixed with the soil as a means to raise calcium content in the soil; and likewise for making a banana peel solution (soaking peel in water overnight) to raise potassium content in the soil. 

Common Garden Pests

1) White Flies

Whiteflies are commonly found on the undersides of leaves. They develop themselves into clusters attacking and sickening plants as they excrete a form of sweet honey dew, which attracts both ants and sooty mould fungi. Infested plants may show a spectrum of symptoms such as yellowing of leaves or veins, yellowing mosaic patterns on the leaves, as well as the curling of leaves. Sooty mould will very likely be present too.

Edible plants such as leafy vegetables (i.e. bayam, and fruiting vegetables such as brinjal, chilli, lady’s finger, long bean and tomato) are vulnerable victims to white flies infestation.

White Flies in Singapore leaves

To resolve, the simplest and most effective way would be to remove any infested part of the plant (can infect the stem/ branch portion besides the underside of leaves) in order to prevent migration of whiteflies onto its nearby plants. After removing the infested parts of the plant, consider spraying some neem oil solution onto the underside of the leaves to rid any remnant whiteflies which were not visible.

Another important routine to prevent infestation would be to remove weeds regularly so as to reduce whitefly populations. 

Yellow sticky traps too, can be very effective to trap adult whiteflies, thereby reducing whitefly populations.

2) Insects (Caterpillars, moths, grasshoppers, stick insects)

Insects can wipe out your painstakingly grown edible plants overnight. Yes, unfortunately all it takes is one night to nullify all the time and effort placed into growing those lovely greens.

Depending on how large the insects are which dictate what they will choose to eat, most insects go straight for the leaves! Being soft and tender, leaves are the choice pick of both small and large insects. 

A simple and effective *home remedy* to deter a plethora of insects would be to spray a chilli + garlic skin solution. This would ensure that insects (or whiteflies) would no longer fancy your greens. 

Recipe for chilli + garlic solution: Chillies, garlic skin, a squirt of dish-washing detergent, water, a spray bottle (500-600ml would be ideal)

  1. Cut 7-8 medium sized chillies into chunks; and
  2. With 500ml of water, boil cut chillies and garlic skin on stove top for 15mins (once boiled, turn heat down to a gentle simmer);
  3. After boiling for 15mins, turn the heat off and let it cool.
  4. Strain boiled liquid and transfer solution into spray bottle; thereafter
  5. Add a squirt of dishwashing detergent to the bottle and top bottle up with water;
  6. Shake well to combine, and it is ready for application onto the plants.

This solution can be used for both prevention as well as curing of infestations.